Dear reader, May
2005
there are a
couple of things I would like to tell you before you tackle this
translation.
Firstly, I am a
Òshark agerÓ and what I thought was a reasonable knowledge about sharks in all
aspects turned out to be a rather sorry one. I realised that I am definitely not a taxonomist, a
ÒhistologistÓ and an anatomist. I
bow with respect to the good old fashioned all-round scientist! I especially
battled with the teeth structure and the intestine part, digging out school
memories which I thought hadnÕt exist anymore. Some of his descriptions I didnÕt understand myself which I
am sure will be reflected in the translation. Most of the nitty-gritty terms, again especially in the
teeth and intestine section, one canÕt find in a dictionary and one would only
know, I suppose, with the right Òinsider knowledgeÓ. I even asked a dentist, trying to get an English translation
for the things I tried to describe to him, without much success, unfortunately. So I have to apologise for some of the
sections. I do hope that with the
help of the Figures you will be able to work out what I (the author) am (is)
talking about.
Secondly, I
decided to translate all the text literally, so the English will be not up to
scratch. On very few occasions I
tired to translate the meaning of the sentence in a more modern English. On few occasions text was not
translated, which is mentioned.
Some comments (doubts, questions, non-understanding of the German text,
interpretations) are given using footnotes. Please note that the original text also has footnotes. Words
in italic in brackets are not in the original text. They are (mostly) added for better readability or to give
alternatives, e.g. tube (duct/tunnel) - take your pick. Please note that the original text also uses brackets. Literal translation means that I am at
a loss as how to translate correctly.
Contribution to the natural history of
East-Asia.
Published (edited) by Dr. F Doflein.
On two enormous embryos from Lamna.
From Johannes Lohberger
From the Zoological Institute of the University
of Leipzig.
With 5 plates.
In his travel description: ÒEast-Asia travel,
experiences and observations of a nature scientist in China, Japan and Ceylon
(1906) Doflein reports:
Ò One of the most surprising discoveries for me was the egg
of a giant shark[1].
I received it several times from fishermen, without ever getting the
mother-animal which belongs to it.
Those eggs were taken out from the mother-animal, which obviously
belongs to the live bearing sharks; with their enormous yolk mass they
constitute the, to date, biggest known eggs from live bearing animals . They are considerably bigger than
ostrich eggs and also distinguished from all known shark eggs by (the fact
that) the embryo is not
connected with the yolk sack by a long, cord-like umbilical cord but is growing
up directly on (top of it) it. Ó
Those two shark eggs, amongst it the, to date,
biggest known vertebrate egg, fell into the hands of my highly admired teacher,
the Prof. Dr. Chum. He was kindly
enough to leave the two specimens to me with the determination[2],
to closer investigate their anatomy and to determine in detail which species
they belong to. For this kindness and the advice and
help. . . . .
. (two sentences of
heart gripping acknowledgements which I didnÕt translate).
In the beginning it would like to be remarked, that
the two embryos are completely identical despite their difference in size, so
that for the preparation to examine the internal anatomy I could restrict myself
to the smaller specimen. For the
examination of the external features, mainly the head, the bigger animal was
more suitable, as one finds the natural features, despite the preservation,
good and better conserved as in the smaller one.
The later examination will show that they belong to
the genus Lamna. Thus, they will
be named as such in the prior sections.
Also, in connection with the yolk sack, a remark
must be pre-mentioned. As one will
find out, one does not deal with yolk sacks in the usual meaning. If therefore Doflein regards it as the
yolk sack which normally occurs with embryos and says that the embryo sits
directly on it, in contradiction with all other known shark eggs, so it looks
like he was deceived. This
deception, however, is easy to explain with the merely external (superficial) examination (observation) of the embryo. Thus, to eliminate all errors a priori,
it seems advisable, to use a different expression. The expression Òyolk stomachÓ will be proposed. Why this particular term was chosen,
will be seen in one of the later sections.
II.
External features
(Fig. 1-3.)
After the decanting of the preserving alcohol, the
bigger of the two specimens, also a unique specimen amongst the vertebrate eggs
in aspect of size, has a mass of 2. 680 kg. Even if one subtracts a part of the penetrated alcohol, one
can still determine from the rest of the mass of our embryo that it is enormous
and also creditable, when Braus (1906) writes the following:
Ò Doflein (1906, a. a. O. [3]
, S. 267/68) described the, to date, biggest known vertebrate egg, also of a
shark, but from an unknown species in Japan. The yolk of the big, nearly fully developed embryos (a
Carcharhid species[4]) measures
along the longitudinal axis 22 cm.
The measurement along the lateral (transverse) axis, however, is considerably
shorter. Mr colleague Doflein was
extremely kind to show me the original specimens this autumn. The width is 13-14 cm. The strong flattening is possibly
caused by the preservation.
Nevertheless, the size off this yellow-egg (literal translation) can stand closely behind those which
were produced by Dinornis and Aepyornis, as far as we can estimate this from
the well preserved shells of those eggs (found in) the in the sand of New Zealand. Ó
As Braus previously mentioned, the longitudinal
axis of the nice egg-shaped yolk stomach is nearly 22 cm. The considerably smaller lateral axis
has a length of 12.3 cm. This
strong flattening which can be observed especially in the bigger specimen, is
surely , as Braus also mentions, due to the preservation. The - also considerably big - embryo
sits with nearly one third (of its size) on the yolk stomach. It measures from the tip of the snout to the tip of the tail
55.3 cm. The - nearly continuously
- cylindrical body has a width of 6.3 cm in the position where it sits on the
yolk stomach.
The measurements are naturally smaller in the
smaller object. The total mass of
the egg is 1.070 kg. The
longitudinal axis of the also egg-shaped yolk stomach is 14.9 cm and the
lateral axis 9.5 cm. In this case
it seems that the preservation did not cause a heavy flattening. The length of the embryo is 42.8 cm. The width in the above mentioned
position is 5.9 cm.
A summary of all measurements, including those not
yet mentioned, will be given at the end of this section.
After (behind) the head, the body of our Lamni (plural for
the two Lamna specimens, literal translation) naturally becomes wider and towards the tail
narrower. The head has the shape
of a short, blunt cone with the upper part dyed (literal translation) dark (in the preserved object it is
blue-grey) and the lower
part light (slightly yellow).
Nearly at the tip of the head towards the lower part (ventral side) and totally isolated from the mouth opening, are
two nostrils in a distance of 2.1 cm and 1.4 cm, respectively, from each other,
both are partly obscured by small triangular nasal flaps. Close under them, relatively parallel
to the main axis of the cone-like head one gets to the mouth opening. It is big and, as a cut parallel to the
headcone, it is half-moon-shaped.
Although the blunt tip of the head, the rostrum, is protruding a small
bit over the mouth, one can still call the mouth opening with a bigger right
terminal, because the opening lies towards the front, therefore when viewing
the embryo it can be seen directly on the tip of the head. This would not be the case if it would
lie, as described (indicated) by GŸnther, towards below, which can be observed as an extreme in
Mustelus laevis.
Fairly (somewhat) over the corners of the mouth and a small
distance after the nostrils one finds the relatively large eyes. In the outer skin they build a circular
cutting with a diameter of 1.2 cm
and 0.8 cm ,respectively, which, in the case of the smaller objects due
to the preservation, can not be guessed as such that easily[5]. Even with the most meticulous
investigation, no nictating membrane could be discovered.
The head goes (changes) without any interruption (pause,
break) into the neck,
which has the same colour like the head and which possesses 5 relatively wide
gill slits on either side. They
are in front of the pectoral fins and reduce their size towards the back. The width of the first gill opening is
nearly the same as the distance from the first to the last gill slit. The foremost gill slits go so far
towards the ventral side that they come close to its middle line. The length of the foremost gill slits
is 4 cm and 5.5 cm, respectively, those of the back, the smallest, 2.5 cm and
3.2 cm, respectively.
The position and the whole external features of the
gill slits already give, after Jaekel (1890), a small hint towards the families
our embryos may belong and to which they will not. After JaeckelÕs statement they can not belong to the
families of Carcharhids (in contradiction with BrausÕ assumption) and Scylliids
and Cestracion. In those, one
finds five short gill slits of which the foremost ones sit in front of the
pectoral, the rear (posterior) ones over the pectoral fin.
Also, the foremost ones reach down to the insertion point of the
pectoral fin. In some forms (species), the last slit seem to be built back (literal
translation), or is so close to the second last that it
is externally barely visible next to the second last, therefor one sees only
four gill slits. Of those, there
are then only two situated before the pectoral fin. The same way we found the gill slits in our embryos was
found by Jaeckel in the Lamnids and Spinacids including Pristiophorus, in which
always all openings are in front of the pectoral fin, mostly very long and
reaching below the basis of the pectoral fins.
In our Lamni one has difficulty to find their
squirt holes (spiracles ?). When one very
carefully examines, one can find on both sides, approximately in the middle of
the connecting line between the back
(posterior)
edge of the eye and the topmost corner of the first gill slit, each one
pore-like depression. Both embryos
have them in the same position, which perhaps disappear completely in the fully
grown animal. They do not seem to
be deep as we could only insert a probe for a little bit. With a cut they disappear very quickly
under the surface[6].
The cylindrical-shaped torso is approximately twice
the length of the head and neck and becomes smaller towards the end. On the upper part and lower part (dorsal
and ventral) it also
has the same coloration as the head and neck. Whereas those two colorations slowly merges into each other,
at the back (posterior) part of the torso, they are sharply separated on both
sides with a keel.
Of most selachii is known that their dorsal area
shows a certain amount of roughness due to a number of Òskin teethÓ (literal
translation). Now, our embryos were investigated for
those placoid scales (literal translation). Dyed (stained) cuts were made from part of skin pieces and some
of those pieces were treated with warmed, concentrated potash (caustic lye).
But neither the cut series nor the treatment with potash showed apparent
skin teeth.
The light coloration of the belly side merges on to
the egg-like yolk stomach, on which the embryo sits from the middle of the neck
to the middle of the torso, till the anal opening. The, as a result, missing umbilical cord and the significant
size of the yolk stomach leave our Lamni, as also mentioned by Doflein himself,
different from all, to date, known shark eggs.
Directly behind the last gill slit and behind the
lower edge sit the two pectoral fins.
They build a triangle with a rounded tip and a slightly cut out
posterior edge. As the front edge
is slightly bent, the whole fin appears slightly curved. Both edges are only a little bit longer
than the base. The pectoral fins
can not be called particularly big.
Their lower part is coloured very light and the upper part grey with the
exemption of the lighter edges.
Above the backmost (posterior) end of the pectoral fins starts the
first dorsal fin. Its front edge
builds a blunt, rounded angle with the back area, its back edge a pointed
angle. It has nearly the same form
than the pectoral fins, only one third shorter. It does not have a spine. Its colour is white-yellow: only the free edges appear grey.
Approximately two lengths[7]
behind the dorsal fin, directly behind the insertion of the yolk stomach,
begins the completely lightly coloured belly (pelvic) fins. They have half the length of the pectoral fins and the shape
of an elongated rectangle. The one
pair of small sides are grown on (the torso) close to each other, so that the inner, parallel
lying broad sides tightly confine the front halves of the anal opening[8].
Those inner long sides are in their back half bent (scalloped) slightly towards the anus. The outer long sides, however, proceed
parallel to the just mentioned inner ones, so that the whole pelvic fins assume
a bent (scalloped)
form. In addition, the free edges
are rounded and the free short sides are cut out slightly round.
Approximately in the same distance, in which the
first dorsal fin is distanced from the tip of the snout, we will meet - behind
the first of the second dorsal fin and exactly opposite it, the anal fin. Both are very small and the same in
shape and of light coloration.
They have the shape of small rectangles, their attached (grown on) edges are one third smaller than the
base of the first dorsal fin.
Their edges are straight and build with the dorsal and belly line,
respectively, one frontal blunt and one posterior pointed angle.
The body goes gradually into the tail, which is
divided distinctively by a keel into an upper and a lower part. A short distance after the second
dorsal fin, the tail broadens into the tail fin. It consists of an upper and a lower lobe, the lower lobe is
half the size of the upper lobe.
Both build a pointed angle to one another. At the root of the tail fin there is, dorsal and ventral
each, a distinct groove or scar impressed (precaudal notch ?). The lower lobe is short and broad with rounded
edges and sides, with the tip pointing back. The upper lobe, on the other hand, is long, with a broad
basis and pointed towards the back.
Shortly before the outermost tip, it has a triangular cutting. Also, the whole upper lobe is bent
sickle-like. Both lobes are light
in their coloration. Only the
outmost edge of the lower lobe is dark grey, nearly black in colour, whereas
the same edge of the upper lobe appears faintly grey.
Measurements
Small
Big
specimen specimen
cm cm
Total length of the embryo............................. 42.8 55.3
Width of the embryo (at the location of
the yolk stomach 5.6 6.3
Longitudinal axis of yolk stomach...................... 14.9 21. 1
Lateral (or transverse) axis of yolk stomach.......... 9.5 12.3
Distance between mouth ends............................ 3.8 4.2
Distance between nostrils.............................. 1.4 2.1
Diameter of eyes....................................... 0.8 1.2
Distance between the first and the last
gill opening... 3.6 3.8
Distance between the tip of the head and
the yolk stomach 8.9 12.4
Distance between the tail tip and yolk
stomach......... 21.1 26.7
Distance between tip of head to first
dorsal fin....... 13.1 17.8
Distance between first dorsal and second
dorsal fin.... 12.3 17.8
Distance between tip of head to pectoral
fins.......... 9.7 13.9
Distance between pectoral fins and
pelvic fins (anus).. 9.7 13.1
Distance between pelvic fins and anal
fins............. 5.3 6.5
Height of the first dorsal fin......................... 2.1 3.2
Length of the first dorsal fin......................... 2.5 4.3
Length of the second dorsal fin........................ 1.3 1.7
Length of pectoral fins................................ 3.5 5.4
Length of pelvis fins................................. 2.2 2.9
Length of anal fins.................................... 1.4 1.8
Length of tail fin (upper lobe)........................ 11.5 14.7
Length of tail fin (lower lobe)....................... 5.4 8.2
Base of the first dorsal fin........................... 2.5 4.3
Base of the second dorsal fin.......................... 0.7 1.0
Base of pectoral fins.................................. 2.1 3.0
Base of pelvic fins.................................... 1.0 1.6
Base of anal fins...................................... 0.7 1.0
Base of tail fin....................................... 1.4 1.8
III. Situs viscerum (the position of the intestines ?)
(Fig. 4-6.)
In order to get to the internal organs, the
peritoneal cavity was opened from the right side and at the position where the
embryo and the yolk stomach merge into each other. The resulting skin flap can easily be flapped back over the
yolk stomach as Figure 4 shows.
That is (because),
the external skin of the animal does stretch around the yolk stomach, without
being somehow fused (grown together, attached) with it.
Most conspicuous, the enormous bloated yolk stomach
(do) steps into forefront view.
Even now its red-yellow colour is conspicuous, which indicated the
presence of a plentiful amount of yolk mass. Also, a number of stronger blood vessels (g), which appear
in the preserved state white, are clearly recognisable in the wall of the yolk
stomach.
As we are cutting open, already the right liver
lobe, which still lies a small amount over (on top of) the yolk stomach, is coming towards us
from askew under the right pectoral fin (Br). From the still partly obscured peritoneal cavity protrudes,
under this liver lobe, the spiral intestine (s). Already, this piece, that reaches from the liver lobe till
the pelvic fins, gives an indication as to the size of the spiral intestine,
one can already see clearly from the outside its internal spiral-flap (valve) building. In a quite short distance and parallel to this spiral
intestine stretches out (draws out, drags out) a second part of the intestine (p), which also
emerges under the liver lobe, (then) stretches out (draws out, drags out) over the yolk stomach and suddenly
disappears from the surface (m. p.) shortly before the pelvic fins (Ba.). Later, more detailed investigation will
show that at this point it leads into the yolk stomach. It will be established as the ascending
part of the stomach. On it is
attached , along the whole side of the spiral intestine, an organ (m),
elongated and partly divided into smaller pieces, which is nothing else than a
branch of the still to be mentioned spleen.
If we proceed with the above mentioned cut on the
left side, one can see the following picture (Fig. 5): underneath the left
pectoral fin, completely analogue to the right, protrudes the left liver lobe
and lies also partly over the yolk stomach. This (yolk stomach) fills, of course, here also fully the opening
caused by the cut, and it is also recognisable here by is richness in yolk mass
and blood vessels (g). But, where
at the right side the spiral intestine and the second into the yolk stomach
leading part lies, lies here an organ, that divides (falls apart into pieces) into many small parts. It is the spleen (m), which is divided
into many small spleens, as has already been observed in some sharks. In our Lamni it lies partly left,
partly dorsal- area-like on the yolk stomach till to the spiral intestine, goes
around its (intestine)
back part in a circle and sends the already mentioned branch to the ascending
part of the stomach (m).
This whole assembly of the internal organs seems
different compared with other sharks.
The organs have mainly an unusual position, which is only, and only, caused
by the yolk stomach. If one
compares the situs viscerus of an older embryo of Mustelus leavis, the
following picture emerges: both enormous liver lobes protrude (emerge) underneath the pectoral fins. They have to be put aside a
considerable part to fully see the other organs. The other organs are in a row from left to right as follows:
the spiral intestine stretches out (draws out, drags) from the cloaca nearly the whole length
of the peritoneal cavity. Shortly
before the root of the right liver lobe it turns around (pylorus) and flows
into (merges into)
the ascending, thinner parts of the u-shaped stomach. Along this section runs on the side of the spiral intestine
the spleen, which is quite small till the back part of the ascending stomach
shank (part), but
forms itself at the knee of the u-shaped stomach into a broader organ. Under the pylorus, one can see to a
small degree the pancreas which then disappears behind the spiral intestine.
If one imagines in this situs the ascending part of
the stomach as increasing in extension (size), than there is the question that the other organs
would be pressed to the side and to the back. This would then show the picture which the situs viscerum of
our Lamni is showing (Fig. 4-6).
IV. Digestive tracts
(Fig. 8-21.)
a) Mouth (Fig. 8-10.)
As we saw earlier on, the mouth of our shark lies
quite at the end of the head. His
size can draw the conclusion of the later (evident) greediness (voracity) of the Lamna species, which (the conclusion) is strengthened by the few, but
externally visible, teeth. The
upper and the lower jaw, both half-moon shaped, are externally nearly smoothly covered with the skin and
there is only a slight hint of lip building (Fig. 12 li) to observe. However, on the insides of both jaws
the skin widens (expands)
to lumps (swellings, humps, folds), which snuggle up closely to the jaws and which
hide the young developing teeth[9] under them. One can easily rip them (the folds) off their attached sites and thus make
the young rows of teeth visible.
The latter is only possible if one - in the process - rips off the
tooth ridge[10] from the young teeth. Thereafter, those skin folds build the developing teeth
themselves. Those folds elongate
themselves into the inner part of the mouth (throat) to the inner mouthwrinkles (literal translation, mouth folds).
The mouthwrinkle of the lower jaw (mu) is relatively insignificant,
whereas that of the upper jaw reaches nearly to the middle of the mouth (throat).
In this way, the mouth (throat) is closed bag-like with a relatively closed
mouth. One can make the
speculation that this arrangement prevents the yolk stomach to get
outside. Because in our Lamni the yolk
stomach is a substitute for the stomach, there is easily the possibility that,
through pressure or other reasons, the yolk mass is emerging through the short
oesophagus into the mouth
cavity. But here, this
mouthwrinkle acts as a flap and prevents the yolk mass to get outside. In later life in particular this fold
will be responsible to prevent the
return (retreat) of
swallowed water from the mouth cavity. I have found the mentioning of a similar
mouthwrinkle (fold)
only once and this in ÒMŸller and Henle,
Systematic description of plagiostomaÓ (1841) where in the family of
Alopeciae a Òmouth fold/wrinkleÓ is mentioned. But more information about its form and function is missing
completely.
Stannius (1846, p. 88) attributes mucous membrane folds (literal translation), lying behind the jaws, to many
teleosts, which prevent the return of swallowed water from the mouth cavity.
Amongst the histological nature of this fold is remarkable, that the epithelial cell
layer of the dorsal side is nearly three times thicker than on the other
side. One can also observe in this
cell layer bud-like clusters of cells.
They are similar to taste buds, unfortunately the preservation is not
such that one can declare with confidence the presence of taste buds and
examine the buds closer.
The broad gill
slits (ksp), which externally reach already pretty far to the middle of the
neck, leave free in the inside of the mouth an even smaller middle piece. Their width also, is equal to the broad
external gill openings[11].
In front of the first gill slit rises the tongue
(zu) which is far bigger in our specimens than one would be used to from
fishes. The fish tongue is known
as a mere rudimentary (thing) of a tongue and as completely immobile (Hšrschelmann, 1866). But the tongue of our Lamna is surely
not completely without function; because in sagittal cuts one discovers a
supporting cartilage (Kn) which is developed far to the front. On it adds on a broad muscle (mus),
which, without doubt, enables no small movability of the tongue[12]. For a conscious[13]
movement vouches the
distinctively developed lateral stripes of the muscle.
The big throat, which rather suddenly narrows
itself into the oesophagus is lined with mucous membrane of the mouth. This is, as evolution shows, nothing
else than the external skin and as such it could carry the - for sharks peculiar
- skin teeth (dermal denticles). Now, we have not found
on our two sharks any sign of dermal denticles in the external skin, so that therefore
we can assume that there are also none in the mucous membrane of the mouth
(buccle mucous membrane
?). And really, there are no
developed dental teeth in it. On
cuts through the buccle mucous membrane, however, one finds peculiar, wart-like
forms (Fig. 9 and 10 hz) which are protruding from the epidermis and which one
must see as back-developed skin teeth. They are distributed in irregular
distances on the skin and are partly with one hump, partly with two humps. That such forms have been found in some
sharks is mentioned , e.g., by Hertwig in his paper ÒOn the structure and
development of placoid scales and the teeth of selachiiÓ (1874) where he
writes: ÓAccording to Leydig they (the skin teeth in the mouth) occur also, apart from Hexanchus, in
Raja clavata, but have on the other hand not been found in Scyllium and
Scymnus. Here they are substituted by wart-like or filament
(cord-like),
non-calcified papillae, which have the same triangular form as the teeth of
those animals and which would represent completely developed teeth if they
would be covered by a cap of calcium saltsÓ.
b) Teeth (Fig. 11-12.)
The second type of teeth in the buccle mucous
membrane is restricted to the upper and lower jaw. Although those differ only a little from the so far
described selachii teeth, they should be described here for completionÕs sake.
In our two
Lamnids, the number of externally visible teeth is still very low (Fig. 8). However, they give information on their form and arrangement
which is important for the later taxonomic determination.
It is, however, as difficult as it is brave to use
those teeth of -granted nearly fully developed- embryos too strictly (rigorously) in a systematical determination. This will also be considered later in
the taxonomic determination of the species of our Lamni. The present teeth are mainly irregular
distributed in both jaws; a regular arrangement in rows is not visible
yet. Some are protruding
completely, whereas others are only partially visible. But even those few teeth give a clue to
the later strong set of teeth (denture).
Close to the symphyses (Fig 8 sy), which are externally visible marked and which do not carry
any middle teeth, different circumstances attract notice. In the upper jaw, the first two teeth
on both sides of the symphysis are markedly smaller than the other teeth of the
denture, in particular also smaller than the following third tooth. After this one a markedly smaller tooth
follows, whereas all the following are again bigger. In the lower jaw this arrangement is not there. Here, there is only one small tooth on
both sides of the symphysis.
There are also differences in the form of the
teeth. The oldest are strong,
squat (stocky) and
markedly awl-like with tips bent backward (Fig. 11 a). The somewhat younger teeth (b), those
which are still sitting in the inner margin of the jaw, show still the awl
shape, but are much slimmer and show a lateral flattening. This flattening is
completely developed in the even younger teeth which still sit partly in the
tooth ridge. On
those, there is not the slightest evidence of awl-shape to detect.
The base of the teeth at hand is simple and
conical; the two small cusps of other selachii teeth are missing in those
teeth. As all selachii teeth, they
are also only embedded with their base in the mucous membrane which covers the
jaw arch, they therefore are not connected to the jaw cartilage (Fig. 12).
This loose attachment causes a very fast abrasion
of the teeth. The manifold and
never-ending supply, however, is provided by many rows of young teeth. One can
find in the upper jaw 14 of such teeth rows, in the lower jaw 13, they contain
spare teeth in various developing stages.
It was mentioned already that the inner sides of the jaws become visible
when folding back the mucous membrane folds. But to get to know their developmental stages, which is only
possible with microscopic preparation, lateral cuts were made through the
jaw. One of the most complete cuts
form the lower jaw can be seen in Figure 12, which will inform about nearly
everything of importance.
Here attracts notice firstly the jaw cartilage (kn),
which builds a perpendicular angle and which is bordered by a string of pigment
cells (pig). On its ventral side,
close to the edge of the jaw, the connecting tissue shows a distinct, if small,
lip building (li), which has been mentioned earlier. One must therefore agree with Hertwig (1874) and not Jentsch
(1897), when he gives the selachii a lower jaw lip. Jentsch, however, denies this. In the corner of the jaw cartilage one meets a row of developing teeth (z1 -zb ) in
various stages of development. The
young teeth decrease in age from
the jaw edge to the base of the corner ground. The oldest tooth (z1 ), sitting closely near to
the jaw edge, is nearly completely disconnected (literal translation) from the area of the tooth ridge (zl),
therefore relatively functional (operational), whereas the other four tooth ridges (z2 - z5 ) still completely
protrude into the epithelial ridge[14]. The youngest developing tooth (z5 ) comprises an elongated papilla, over
which rises the cylinder-cell-layer (literal translation) of the epithelium (ce) which is filled
up densely with mesenchyme cells till close to the epithelium (my). The next oldest papilla (z4 )
is also covered with epithelium, but is not so densely filled up with
mesenchyme cells anymore, in particular at the base. Also, the latter (mesenchyme cells) do not tower up till the
epithelium at the top of the papillae.
In its place a light mass (d) has been built, which shows a visible, but
very fine longitudinal striation.
This mass is the fist anlage[15] of the
dentine with the manifold dentine canals (ducts) (dentinal, canaliculi dentales ?). The third youngest developing tooth (teeth) (z3 ) is even more
elongated and the dentine is significantly further developed. It is thickest at the tip and reaches
from there down over the whole papilla, whilst it gets thinner as it goes
down. Here also, the dentine ducts
appear as a very fine striation.
The next developing tooth (z2 ) is significantly nearer to
the fully developed stage. It is
visibly sharpened (pointed) and has already assumed nearly the final form. The dentine (d) has also experienced a
significant change. It has
broadened in the whole papilla till the base in the form of dentine cords,
which show between them broad dentine canals (ducts) (dr). The latter are filled with a number of mesenchyme
cells. This external dentine layer
has been stained conspicuously
strong, but only in this anlage, and goes (proceeds) into a remarkably lighter layer
(s(v)). As the light layer at the
tooth tip broadens to a summit (literal translation), one can regard this as the layer
which is named by many authors as dental enamel, by some others, who deny
enamel in shark tooth, as vitrodentin.
This developing tooth is therefore equipped with everything, which the
fully developed tooth has.
The structure of the developed teeth show small
variations from the ones described so far. That their dentine tubes (ducts/tunnels) are rather wide, has been mentioned already. They sieve the dentine relatively
irregular and go not, as is normally the case, from a distinct centre, the
pulpa, in all directions. Also,
they do not branch out as the branches of trees, where they get narrower and
finer. One can not speak of a
distinct pulpa in any (of those) teeth.
This is already known from several sharks,
especially of the genus Lamna. It
is interesting and with this attention is drawn to it, that in this point the
genus Lamna is distinctively different from the genus Carcharias. According to Treuenfels, Jaeckel found
that Carcharhids and Lamnids
differ in the structure of the tartar . Whereas in the Lamnids the dentine small canals come from a
multiple branched, net-like pulpa cavity, they take exit in the Carcharhids
from a uniform cavity situated in the middle. This structure is constant in the various teeth forms and
separates both families sharply (see remark p. 4).
The branches of the dentine ducts (tubes/tunnels) happens in our Lamna such, that
directly from the broad dentine ducts (tubes/tunnels) a number of very fine dentine ducts (tubes/tunnels) go off, that the transition is
therefore suddenly and does not happen gradually like the branches in the
trees. They are most numerous in
the outer dentine layer.
c) Oesophagus (Fig. 6.)
The wide mouth cavity goes suddenly into a
extremely narrow and short oesophagus.
It shows a distinct longitudinal folding, in which some folds protrude
as bands with a minimum width of 1 mm.
Its wall (linings)
are very thick and lined with very low (short) paving epithelium[16].
On a moderately thick mucous membrane follows a small longitudinal
muscle layer and after that a circular muscle layer, four times as thick. The muscle skin consists, as in all
investigated sharks and rays, of lateral striped muscles(striated muscle ?).
In the whole length of the oesophagus, the mucous membrane possesses a
quite big number of glands, which one can see in different locations emptying
into (leads into)
outside. Several times, the
microscopic cuts show those glands without lining epithelium due to the bad
preservation and the applied preparation, so that it looks like they are not
any glands. However, in most
places they are distinctively lined with epithelium, so that the presence of
glands in the oesophagus of the present embryos is without doubt.
d) Stomach (yolk stomach) (Fig. 1-6.)
The narrow oesophagus goes funnel-like into the
descending, enormous widened part of the stomach. This cardia part (do) is filled bursting with yolk and this
is the reason why the name yolk stomach was given. It substitutes the yolk sack as we will still see. A proper (true) u-shaped stomach, as it is named in
the sharks, is out of the question in our Lamni; because the descending cardia
part and the ascending pylorus part (p) of the stomach are very different in
their size.
The thick wall (lining) of the oesophagus goes into (merges
into) the extraordinary
thin stomach wall as suddenly, as the oesophagus widens into the stomach. This
thin wall (lining)
is remarkable for a stomach, but even much more so for the enormous big stomach
of our embryo. One could therefore
doubt the firmness (stability) of the yolk stomach, if it would not be enclosed by a firm (stable), external abdominal wall. Surely, this thin stomach wall will get
thicker once the whole yolk mass is utilised and the stomach can assume its
normal shape.
Despite the maceration one can recognise in most
places the circular and longitudinal layer of the muscularis (smooth and
striated muscle ?). A serosa is also there, but a hint of
glands is not to be stated. Only a
big number of narrow and wide blood vessels (g) permeate (flow through) this thin skin, which was already mentioned as
externally visible. Surely it
would not be completely without purpose that those blood vessels in the present
organ appear in this number. It is
with certainty to assume, that these vessels have the function to resorb the
immense yolk mass for the feeding of the embryos. But this is the same procedure as is happening in the yolk
sacks of other shark embryos.
Therefore the yolk stomach of our sharks depicts a yolk sack in the
common (usual) sense
not morphological , but nevertheless physiologically. It is then explainable, why we could not find glands in the
stomach wall, which are redundant in such a nutrition (feeding) at this stage. They will develop later, when the
stomach begins its real function.
But how does the amount of food yolk get into the
stomach and what is the reason for this interesting case of adaptation, that
the stomach takes over the function of the yolk sack? Those questions are answered by Swenander (1907) who, due to
favourable findings, was in a position to give information on the whole state
of affairs.
During his stay in Trondhjem in January 1904 he got
a female Lamna cornubica, which, as it emerged, contained four embryos, two in
each uterine division of the oviduct.
Those embryos had a length of 5.5-6 cm and possessed very strongly
developed external gills. What,
however, surprised most, was that even in this stadium the yolk stomach was as
good as completely vanished.
Externally, there was of it only a hardly millimetre long rest on the
stomach (ventral)
side present and internally there was only the pitiful remains of the ductus
vitello-intestinalis to find. The
feeding canal (literal translation) was nearly completely empty of food. Apart from these embryos, altogether
slightly over 40 things of peculiar shapes were found in the uterus, which
proved to be, after closer examination, egg piles enclosed with a common cover (sheat/membrane).
The cover is relatively
thin, but strong and slightly brown.
Some time after this, Swenander was sent four more
embryos which were taken from a caught Lamna cornubica closely before (out
of) Trondhjem. These embryos had a length of approximately
30 cm, in which they are not even close to our Lamni. The external gills had disappeared. The most conspicuous, however, was that
they had on the stomach (ventral) side big , round protrusions, which looked after
the first glimpse like a slightly removed (detached) yolk sack.
That this, however, was not one, was distinctly evident after cutting
this kind of embryo in half. The
mentioned protrusion is very simply a protrusion of the body wall, caused by
the outrageously extended stomach.
This one turned out to be filled, including with the oesophagus, in
particular with strongly compressed yolk mass. With closer examination it was shown that in the middle of
the yolk mass enclosed in the stomach, there were lying two egg capsules which
were still enclosed by their hull.
Those had the same look as the above mentioned. Herewith the state of affairs was clear
with a bang. The yolk material,
which the embryos need for their further development after the, in a very early
stage, depletion of the yolk stomach, they get from consumption of the egg
capsules lying next to them in the uterus, or their contents.
If we would also cut sagitally through our embryos,
the same picture would emerge, that Swenander gives about the latter mentioned
embryos. Therefore the same situations are evident , which were found by
Swenander in the embryos described by him. As there is not better explanation than that of Swenander,
we must also assume for our Lamni, that they loose their yolk sacks at a very
early stage, still in the womb (uterus), and so loose all food yolk. Would they also been born in this
period, a further prospering for them would be impossible due to their
unfinished development. But nourishment
must be produced, as they stay longer in the uterus. So they devour the eggs which lay next to them in the uterus
and stuff their stomachs full with food yolk. That the yolk stomach, however, experiences this enormous
extension (protrusion),
as we showed in the present, nearly fully developed embryos, is nevertheless
amazing. It should also be pointed
out, that the yolk stomach has assumed the well developed egg shape. This is one reason more, that everybody
who does not know SwenanderÕs observations, sees the yolk stomach externally (superficially) as a real (true) yolk sack. It is therefore explainable when Doflein says, that our two
embryos are distinguished from all, to , known shark eggs, by (the fact) that they sit directly on the yolk
sack without an umbilical cord.
Another case of secondary feeding in shark embryos
in the womb in known already in some viviparous sharks. Johannes MŸller (1840) deserves the
huge merit, to have proven anew, that amongst the viviparous sharks there are
also those where the foetus is intimately connected to the oviduct wall through
a placenta. He named those sharks
vivipara cotylophora, in contrast to the vivipara acotyledona, where the
embryos have no connection with the oviduct, but develop freely in it. It is therefore the vivipara
cotylophora, where a secondary feeding takes place. After the yolk mass is used up, the further development of
the embryo until the complete formation in the womb is organised through a
juice (liquid)
exchange between foetus and mother-animal trough a placenta.
Should our sharks, and therefore also those
described by Swenander (1907), perhaps not formerly have belonged to the
vivipara cotylophora? Should there
the development of a placenta not have happened so that, because the mentioned
vivipara cotylophora are naturally equipped with a dwindling small amount of
food yolk, a new way of nourishment, that is the eating of the neighbouring
eggs, was necessary? It would be
interesting if this speculation could be confirmed through later investigations.
The investigation of the yolk stomach confirms
nearly all statements made on the yolk mass by Joh. MŸller in his paper ÒOn the smooth shark of AristotelesÓ
(1840). The yolk mass of our
embryos consists nearly completely of globular (spherical) particles (corpuscles), of which only a small number is
flattened a little bit. Internal
transverse (lateral/cross) separations (segregations) are not found. But one can notice of the many granules, as also stated by
MŸller, that they lie in one cell which contours differ very much from those of
the grains and which are very irregular.
Often one observes twin forms in the granules, which are already divided
at the edges, but still connected in the middle. Those also lie scattered (solitary) in cells. Due to this twin formation and due to the different sizes of
the grains, MŸller seems to be not wrong, when he sees in this as the
developmental stages of the yolk.
The grains divide themselves, after prior twin forming, into smaller
granules. The relatively small pylorus part (p) opens on to (into) the lateral (to the side) of the
massive cardia parts[17]
It lies, as all other organs belonging to the digestive tract, in its whole
length flat (flattened)
on (top of) the
cardia part, so that it is difficult in the first place externally (superficially)
to see its opening. It is,
however, immediately visible after picking up the pylorus parts of the
stomach. From it till nearly to
the middle, the pylorus part is cylindrical, whereas the remaining part is
flattened till the proper pylorus, which could have been caused through the
pressure of the organs in their preserved state. This flattening is, however, basically really without
meaning. It was only mentioned
because, at the same place where it enters, the internal longitudinal folding
(Fig. 13 lf) dissolves (splits up) gradually into a fine net of folds (furrows) (fn). This longitudinal folding (Fig. 14 lf) starts already in the
cardia part in some distance from the opening place of the pylorus part and
extends until the mentioned place, to then built the net of folds.
When Leydig says that the part of the intestine
lying between stomach and flap (valve) intestine (valvular intestine) - therefore the pylorus part - has a
thinner muscle layer than the stomach (cardia part), so shows the microscope
from lateral (transverse/diagonal) cuts of the pylorus part exactly the
opposite. The lateral as well as
the longitudinal muscle layer (striated and smooth ?) of the mucosa is significantly thicker
than that in the cardia part. The
mucous membrane also shows a certain thickness. It (mucous membrane)
builds, especially away from the opening place, several big folds, which again
split into many small folds. The
big folds are of course the same which we noticed macroscopic. Accordingly, the fine net of folds in
the anterior pylorus part is build from smaller mucous membrane folds. Additionally, one finds, in particular
close to the opening (aperture) place, a number of oval, sometimes also circular glands in different
sizes, of which some distend into a neck and open (into) funnel-shaped. Those glands are lined with cylinder
epithelium till the start of the neck.
According to the statements of Leydig, the stomach glands do not have this
cylinder epithelium, he is, on the contrary (rather), differentiating in the latter a sharp contour towards
outside and a grain-like-cellular content toward inside. Both statements do not prove to be
right for the material at hand. If
one pursues the mucous membrane with a microscope (microscopically) further towards the pylorus, one
observes, that the previously mentioned glands disappear already before the
middle of the pylorus. It seems, however, to be possible that, because a strong
maceration begins simultaneously with this disappearance, the anterior part of
the pylorus has formerly possessed glands.
e) Spiral intestine (Fig.
15-17.)
The transition place of the pylorus part of the
stomach to the spiral intestine (s) builds, as everywhere, the true (proper) pylorus (py). In the existing case it
is narrow and very short, as the spiral intestine descends directly next to the
pylorus part in the peritoneal cavity.[18] At the opening (mouth) place of the pylorus rises in the
inside of the valvular intestine a papilla, in its middle focus sits the true (proper) very narrow opening (pap). Additionally, it should be mentioned
that near the external opening place of the pylorus into the spiral intestine
the ductus choledochus empties (ends/flows) also into the latter. From this opening is, however, macroscopically nothing to be
seen in the inside of the spiral intestine. This shall be closer described later in the observation of
the liver.
The spiral
intestine (s) or also named valvular intestine has indeed roughly the same
length as the pylorus part of the stomach, but has a significant bigger volume
that it. Already with an external
(superficial) examination it is distinguished by
peculiar spiral lines on its surface, which stand perpendicular to the
longitudinal axis and which, in the front part, proceed parallel at a distance
of 1.5 mm and in the last third at
a distance of 2.5 mm. Those spiral
lines are the places of attachment of the spiral fold, which traverses the
spiral intestine in not less than 38 turns (windings).
This is a such a big number of turns, it has so far not been observed in
any spiral intestine. At the same
time, the valvular intestine is not very big, at least in comparison to sharks
with far longer valvular intestine.
The valvular intestine of our shark has a length of 6 cm and an average
(or: at the middle of the intestine) diameter of 2. 5 cm
The spiral fold (sf) begins under the opening place
of the pylorus, therefore, leaves the valvular intestine free in the frontal
part. This valve-free, above
(on top) summit-like
covered part of the spiral intestine is named falsely by many authors (e.g.,
Joh. MŸller, 1844) bursa entiana.
Redeke (1900) speaks out on the real bursa entiana speaks. The further course of the valve is very
analogous to a spiral straicase.
Because its width is only 1 cm, therefore smaller than the diameter of
the valvular intestine, there is an opening of 0.5 cm in the middle. This (opening) continues through the whole length of
the valvular intestine, so that one can see right to the ground from the top,
very similar to some spiral staircases.
In our present spiral fold, however, the opening gets wider towards the
end. The spiral fold decreases in
its width from the 28th turn (calculated from the pylorus), so that already at
the 32nd turn, it has only the width of 0.5 cm. At the last turn it measures only 1 mm and goes fairly close
to the crossing place (transitional place) in the rectum (colon).
According to Joh. MŸller, this spiral fold is to be
referred to as screw-like.
According to him, the external edge of the spiral valve is attached at
the intestine walls like a spiral staircase and its form is screw-like in most
sharks and all rays. The spiral
valve of some sharks from the family of the nictating sharks, in particular
Sphyrna, Carcharias, Thalassorhinus, Galeocerdo, he calls rolled. In it, both the attached and the free
edge proceed straight from the upper end of the valvular intestine towards
below; thereby the valve is rolled around its free edge, which therefore lies
in the middle of the roll. In comparison
with our earlier statements it stand immediately to reason, that this rolled
form of the spiral fold is out of question in our shark. Remarkably is only that this from is
also found in the genus Carcharias.
This fact (case)
gives provisional (temporary) rise to doubt about the correctness of BrausÕ statement, that our
present sharks belong to a species
of Carcharhids (see section: ÒExternal featuresÓ).
Parker distinguishes four typical main forms of
spiral folds. The spiral fold of
our Lamna then belongs to the type A, the simplest form, in which the free edge
of the valve proceeds in the same height as the attached edge in all
turns. The width of the valve does
not exceeds half of the intestine diameter. In type B, the valve reaches till the middle of the
intestine, whereas in type C and D the latter is exceeded, so that all folds
turn themselves backwards (type C) or forwards (type d), respectively. Both, surface as well as resistance,
grows from type A to D. Therefore
both would be present in a very small amount in our present valvular
intestine. Due to the prominent
amount of turns of the spiral fold they can equal, perhaps even exceed, the
surface and resistance of a spiral fold of one of the other types, but with
significant less turns.
The surface of the spiral fold and the surface of
the inner valvular intestine surface contribute substantially to this. Even with the magnifying glass one
observes on both surfaces of the valve a network of thin small folds (Fig. 17
flt) of the mucous membrane, which builds polygons of different sizes, in
particular hexagons and occasionally rather regular ones. Such small folds are also present on
the inner spiral intestine area.
They are as thin as those on the valve, but proceed parallel to each other
and are standing perpendicular to the attached edge of the valve. From this edge they go into (merge into, change into) the mentioned network on the spiral
fold. Those small folds of the
mucous membrane, those of the valve as well as those of the intestine area, are
at the place of the, in most sharks and rays present, villi[19], of which the microscope does not show
the smallest hint in our present animals.
Unfortunately, both the valve as well as the
intestine wall was very macerated.
One can state rather likely, however, the missing of the glands in both,
and one can observe, apart from remains of the muscle layers, the frequent
appearance of blood vessels, of which in particular each two could be found
regularly at the somewhat widened base of the spiral fold. These are the branches of the arteria
and vena omphalomeseraica, which proceed parallel outwards along the ventral
valvular intestine surface and which send a side brach to the left and to the right
after each spiral turn. The same
applies to two - also big - blood vessels, which, however, lie dorsally along
the surface of the spiral intestine (Fig. 15 g). They are externally (superficially) not as distinctively visible as the
veins and arteries on the ventral side, and it can not be determined with
confidence if they also constitute a vein and an artery. Vaguely visible and therefore not to be
referred to with confidence as a real blood vessel, is one such in the free,
slightly thickened edge of the valve.
According to many authors such (a blood vessel) is to be found at this place in most
rays and sharks.
At last it will be mentioned that the valvular
intestine was filled up tightly with half digested yolk mass. Therefore the resorption of the
nutrition yolk is not taken care of alone by the yolk sack (stomach), but is
partly taken over by the other intestine tract, in particular, however, by the
spiral intestine.
Not yet translated are pages 18-39:
f) Final part of intestine and appendix. (Fig. 6, 15, 18-21.)
V. Urogenital system
(Fig. 21-26).
VI. Heart
(Fig. 27-29.)
VII. Breathing apparatus
(Fig. 30, 31.)
Vlll.
Brain and brain nervous system.
(Fig. 32, 33.)
Fore brain [telencephalon].
In-between and middle brain [diencephalon and
mesencephalon].
Hind brain [metencephalon].
"After" ? brain [myselencephalon].
Cranial nerves.
1. Nervus olfactories.[olfactory or 1st cranial
nerve]
2. Nervus opticus.[optic or 2nd cranial nerve]
3. Nervus oculomotorius.[oculomotor or 3rd cranial
nerve]
4. Nervus trochlearis.[trochlearis or 4th cranial
nerve]
5. Nervus trigeminus.[trigeminal of 5th cranial
nerve comprising ohpthalmicus profundus, opthalmicus superficialis, &
maxillary branch]
6. Nervus abducens. [abducens or 6th cranial nerve]
7. Nervus facialis [facial of 7th cranial nerve]
8. Nervus acusticus [auditory or 8th cranial nerve]
9. Nervus glossopharyngens [glossopharyngeal or 9th
cranial nerve]
10. Nervus vagus [vagus or 10th cranial nerve].
IX. Systematic determination
a) After Guenther (1870)
b) After Mueller and Henle (1841)
c) After Hasse (1882)
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Rohon, J. V.
1878. Das Zentralorgan
des Nervensystems der Selachier. Akad. Denkschr., vol. 38. Wien 1878.
Roese, C.
1890. Beitraege zur
vergleichenden Anatomie des Herzens der Wirbeltiere. Morph. Jahrb. 16. 1890.
Roese, C.
1898. Ueber die
verschiedenen Abaenderungen der Hartgewebe bei niederen Wirbeltieren. Anat.
Anz. Bd. XIV. 1898.
Rueckert, J.
1897. Ueber die
Entwicklung des Spiraldarmes bei Selachiern. Archiv fuer Entwickl. Mechanik der
Organismen, W. Roux, IV. Bd. 1897.
Sanders, A.
1886. Contributions to
the Anatomy of the Cental Nevous System in Vertebrate Animals, Part I, Sect. I.
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1875. Das
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Wuerzburg, Bd. II, 1875.
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1876. Ueber den
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1906. Vergleichende Anatomie der Wirbeltiere. Jena 1906.
Xl. Figure captions.
Fig. 1. Larger Lamna-embryo. (1/2 nat. size.)
Fig. 2. Smaller embryo. In natural position. (Ca. 1/2 nat.
size.)
Fig. 3. Smaller embryo. In stretched position. (Ca. 1/2 nat.
size.)
A = anal fin;
Ba = pelvic fins; Br = pectoral fins; Do = yolk stomach; Gr = precaudal pit; ki
= caudal keel; ksp1-5 = 5 gill slits; md = mouth; na = nasal
aperture; o = eyes; R1 = 1st
dorsal fin; R2 = 2nd dorsal fin;
Sch = caudal fin.
Fig. 4. Viscera, right lateral view (2/3 nat.
size).
Fig. 5. Viscera, left lateral view (2/3 nat.
size).
Fig. 6. Intestinal tract with raised spiral
valve (2/3 nat. size).
a.o.m. =
omphalomesenteric artery; app = appendix; Ba = pelvic fins; Br = pectoral fins;
Do = yolk stomach [cardiac stomach filled with yolk]; d. ch = bile duct; e =
colon; l = right or left liver lobe; m
= spleen; mp = pyloric stomach opening [from yolk stomach]; oe =
esophagus; p = pyloric stomach;
[missing py = pyloric valve]; R1 = first dorsal fin; s = valvular intestine
(spiral valve).
Fig. 7. (Had to be deleted!).
Fig. 8. Front view mouth, wide open.
Ksp = gill
slit; mo = buccal fold of upper jaw; mu = buccal fold of lower jaw; ok = upper
jaw; sy = sympheses; uk = lower jaw; z = teeth; zu = tongue.
Fig. 9.
Sagittal section of tongue (x20).
g = vessel; kn
= cartilage; hz = recessive mucous denticle; mus = muscle.
Fig. 10.
Section of mucous membrane in mouth.
ep = epidermis;
g = vessel; hz = wartlike recessive mucous denticles.
Fig. 11. Teeth
of jaw [rather than skin].
a = fully
formed tooth [functional]; b = replacement tooth [mis-labled "d"]; c
= replacement tooth (was still embedded in dental laminae).
Fig. 12. Cross-section through jaw (with dental
lamina). [lower jaw of smaller embryo].
ce = cylinder
ephithelium; d = dentine; dr = dentine tubes; kn = jaw cartilage; li = lip
formation; my = mesenchyme cells; pig = pigment; s (v) enameloid; z1-z5 =
teeth; zl = dental lamina. [z1 has extremely curved crown unlike the
replacement teeth still in the dental lamina. R. Purdy commented that this tooth is similar in form to
those found in stem chondrichthyans and that this curvature may be the
expression of a primitive character which is lost in later generations (of
teeth).
Fig. 13. Transition of longitudinal folds into
net of folds in the pyloric stomach.
Fig. 14. Opening of pyloric stomach from cardiac
stomach.
lf =
longitudinal folds; fn = net of folds?
Fig. 15. Spiral valve, dorsal view. (1 1/2 nat.
size).
Fig. 16. Upper portion of spiral valve. (opened,
1 1/2 nat. size).
Fig. 17. Longitudinal section through wall of
spiral valve, perpendicular to spiral folds.
app = appendix,
d.ch = bile duct; d = colon; flt = mucous fold?; g = vessel; m = spleen; of =
openings between spirals?; ov = ovaries; p = pyloric stomach; pa = pancreas;
pap = papilla with pyloric valve; sf = spiral fold; sw = wall of valvular
intestine [spiral valve].
Fig. 18. Cross?-section of appendix (x50).
Fig. 19. Longitudinal section of appendix (x50).
Fig. 20. Longitudinal section of appendix near
surface (x55).
Fig. 21. Cross-section of appendix near opening.
be = cup
cells?; cy = cylinder cells; dr = glandular tubes; g = vessels; gg = larger
vessels sitting on mucous folds?; mus = muscle layer; sh = mucous membrane; shf
= mucous folds; *) part of gland, free of mucous folds and [blood] vessels.
Fig. 22. Part of spleen.
Fig. 23. Cross-section of spleen.
bi = epidermis
of connective tissue.
Fig. 24. Urogenital organs (nat. size).
Fig. 25. Oviduct and kidneys. Ovaries removed.
(nat. size).
Fig. 26. Kidneys and ureters. Oviduct removed
(x1.5).
Ba = pelvic
fins; dlw = dorsal body cavity wall; e = colon; eil = oviduct; hbl = bladder;
hl = ureter; kl = cloaca, m.eil = opening of oviduct; m.hl = opening of ureter;
ni = kidneys; up = cloacal papilla; oe = esophagus; ov = ovaries.
Fig. 27. Heart with branchial arteries. Ventral
view (x2).
Fig. 28. Heart. Dorsal view.
The auricle is dissected and bent back (x2).
Fig. 29. Conus arteriosus, opened (x6).
1a-5a = 5
branchial arteries; co = conus arteriosus; d.c.d = duct of Cuvier, right; d.c.s
= duct of Cuvier, left; k = ventricle; ka = opening of the 5 branchial arteries
[not used in any figure?]; m = thickened middle part [of pocket-like valves];
m.s.v = sinu-auricular opening; mtr = network of muscles? o.av =
auriculo-ventricular opening; s = thinner lateral part [of pocket-like valves];
sef = tendinous chords; skl = sinu-auricular valves; s.v = sinus venosus; v =
auricle (atrium); va.d = right sinu-auricular valve; va.s = left
sinu-auricualar valve; zw = accessory valves; I-III = transverse rows of
valves; I = pocket-like valves; II, III =
tongue-like valves;
Fig. 30.
Diaphragm [gill pouch or pocket] of 1st and 2nd gill slit on right hand
side. Posterior surface, gill
plates removed (nat. size).
Fig. 31.
Cross-section of gill wall, perpendicular to the longitudinal axis of the
plates (ca. x 50).
baw = Balkenwerk?; bl = gill filaments; bla = afferent
branchial arterioles; blv = efferent branchial arterioles; ep = epibranchial
with cartilaginous branchial rays; kb. a = branchial arch artery. branchial
afferent arteries, arterioles are shown in black for clarity; ker =
ceratobranchial with cartilaginous branchial rays; kh = extra-branchial
cartilage originating at hypo-branchial; kn = button-like end of gill filament
[containing efferent
branchial arteriole] kp = extra-branchial cartilage
originating at pharyngo-branchial; m. add = adductor muscle; m.c = constrictor
muscle; m. i = interbranchial muscle; n.a = nerve branches?; shf = small mucous
membrane folds, dissected irregularly.
Fig. 32. Dorsal view of brain (x4).
Fig. 33. Ventral view of brain (x4).
V =
telencephalon; Z = diencephalon; M = mesencephalon [optic lobes]; H =
metencephalon [cerebellum]; N = myelencephalon [medulla oblangata &
restiform bodies].
Cranial nerves:
n.2 = optic; n.3 = oculomotor; n.4 = trochlear; n.5 = trigeminal; n.6 =
abducens; n.7 = facial; n.8 = auditory [octaval]; n.9 = glossopharyngeal; n.10
= vagal.
boc = eye ball;
cr = restiform bodies; et = eminentiae teretes; hy = pituitary gland; hyst =
epithalamous; li = infundibulum [& asssociated structures?]; lo = olfactory bulb; ltr = lobi
trigemini; p.p = ophthalmicus profundus branch; p.s = superficial ophthalmic
branch; rmm = maxillary branch [of trigeminal]; r.v.t = regio ventriculi
tertii; sla = sulcus longitudinalis anterior; slp = sulcus longitudinalis
posterior; sv = vascular sac; to = olfactory tract [or peduncle].
Fig. 34.
Median, perpendicular cross-section of vertebrae (x6).
a = outer zone;
cd = centrum; fc = notochord; h = haemal arch; i = inner zone; n = neural arch;
st = calcified rays [spokes].
[1]This is the literal translation. I do not know if this means just Òbig sharkÓ or if it is an old German species name.
[2]The German text means either he got the specimens to determine them, or he got the determined specimens.
[3] I donÕt know what this abreviation means in English.
[4]Lohberger has a footnote here saying: ÒWe will see later in the taxonomic determination if it is really a Carcharhid species.Ó
[5]I think he means that the eye can not be seen that easily in the smaller specimen due to preservation.
[6] The meaning here is not clear in German, either they sectioned it poperly or they just cut at the head.
[7] The original text doees nor say what type of lenghts.
[8] I donÕt understand that sentence even in German.
[9] I couldnÕt get an accurate translation for this term. According to the dictonary the translation is Òtooth anlageÓ. Anlage according to s dictonary of biological terms is German and means the 1st structure or cell group indicating development of a part or organ.
[10] I do not know what is meant by the German word (ÒleisteÓ), therefore I could not find a proper translation. Could be moulding, ridge, ledge, ÒcarinaÓ. I could mean that in which the row of teeth is found.
[11] I think he means that the width is the same internally and externally.
[12] He means that this muscle enables quite a moveability of the tongue.
[13]The literal translation means arbitrary, but I think that Òconscious is what he means.
[14] Again the same problem with the translation of the word ÒleisteÓ. I opted again for ridge.
[15] See footnote 9.
[16] Again, as I don not know the different types of epithelium both in German and in English; this is a literal translation.
[17] The original test has plural here. It can however also bee seen as the ancient form of the singular dativ.
[18] Or: as the spiral intestine directly next to the pylorus part descends in the peritoneal cavity.
[19] I think he means villi on a biger scale than the microscopical scale.