DE. A. GUNTHEE’S DESCEIPTION OF CEEATODUS. 
543 
abdomen, but somewhat to the right hand of it. It is a very strong ligament, and, 
behind, firm like a tendon ; there is a slit in it ( b '), on the level of the pelvis, allowing 
of communication between the two sides of the abdominal cavity. The ventral portion 
of the upper part of the intestine is without mesenteric ligament. 
On its dorsal side the intestine is fixed by its attachments to various organs — thus, 
along the median line, to the smooth band of the lung ; more towards the side a portion 
of the testicles or ovaries adheres so firmly to the intestine that it is difficult to separate 
them. Along each side of the intestine lie the generative organs (g), the lung (/) occu- 
pying the place below the vertebral column, without the peritoneal sac. A greater por- 
tion of the lung is visible on the left side than on the right ; and in order to expose it 
to view more fully, we have (at least in the male) to penetrate an extremely singular cel- 
lular tissue (Ji) filling up the interspaces between the peritoneal sac and the walls of the 
abdomen*. Hyrtl appears to have observed a similar tissue in Lepidosiren paradoxa. 
Its cells are very wide, and the meshes so strong that, at the first glance, it may be 
taken for a distinct lung-like organ. 
The kidneys (k) are entirely hidden from view, lying without the peritoneal sac, and 
enveloped in an adipose tissue. They occupy the side of the posterior part of the 
abdominal cavity, forming, with regard to position, merely a continuation of the gene- 
rative organs, to which they are intimately attached. 
The liver ( c ) lies immediately below the diaphragm (d), to which it is attached only- 
in the neighbourhood of the large vessels penetrating the diaphragm ; its upper lobe is 
thin and short, covering the uppermost part of the intestine, and subdivided in the 
middle by the very large and pear-shaped gall-bladder (e), which thus occupies the 
median line of the abdomen. This upper lobe is connected by a narrow bridge with 
a lateral triangular lobe (d) lying on the right side of the intestine ; it is also thin, 
and its tapering posterior end is firmly attached to the extremity of the testicle or ovary 
(g) of the same side. The liver has no other attachment to the intestine, except at the 
place where the ductus choleclochus enters the wall of the latter. 
Intestinal Tract (Plate XXXIX.). 
The buccal cavity is clothed with a soft and rather thin membrane of brown colour, 
the surface of which is uniformly covered with small papillae. A small and short pro- 
minence, a fold of the mucous membrane between the front prongs of the lower molars, 
represents a rudimentary tongue (Plate XXXV. fig. 3, to). The oesophagus (Plate 
XXXIX. fig. 2, oe ) is rather narrow at its commencement, but widens rapidly behind 
the glottis, passing into the stomach (f) without a distinct boundary line. The mem- 
branes of the oesophagus do not show either folds or striae ; but there is on each side 
a longitudinal flat pad (i) of an orange colour ; it is a layer of fat deposited below the 
mucous membrane ; the right pad commences at a short distance behind the glottis, the 
* I have found this tissue much more developed in the male specimen than in the female, in which it would 
interfere with the free passage of the ova through the abdomial cavity. 
MDCCCLXXI. 4 P 
