302 



ZOOLOGY 



&ECT. 



Oe 



MI) 



one large proximal bone, thetibio-fibulare (tb.fb), and two smaller 

 distal (tars. dist). Each digit consists of a metatarsal bone and 

 phalanges, the number of the latter being two, three, four, five, 

 and three. The first and second metatarsals articulate with the 



tibial side of the tibio-fibulare : the 

 rest with the distal tarsals. 



Digestive system. The upper 

 and lower jaws, forming the 

 boundary of the aperture of the 

 mouth, are each provided with a 

 single row of small conical teeth, 

 and there is a patch of similar 

 teeth (palatine teeth) on the pala- 

 tine. On the floor of the mouth- 

 cavity is the tongue, a narrow 

 elongated fleshy organ, bifid in 

 front. 



The stomach (Fig. 912, M, Fig. 

 913, St) is a cylindrical organ, but 

 little wider than the oesophagus, 

 and with thick muscular walls. At 

 the point where the small intestine 

 joins the large intestine or rectum, 

 the latter is produced into a short 

 caecum (Fig. 913, Cos). The liver 

 (Ir) is divided into right and left 

 lobes, and a gall-bladder (Fig. 912, 

 G.B. : Fig. 913, g.b. ; Fig. 914, g.U) 

 lies at the lower margin of the 

 right lobe. The pancreas (pn) is 

 situated in the loop between the 

 stomach and first part of the 

 small intestine or duodenum (du). 

 The stomach is attached to the 

 body- wall by a fold of peritoneum, 

 the mesogaster, the small intestine 

 by a fold termed the mesentery, the 

 rectum by a meso-rectum. From 

 the dorsal surface of the liver to 

 the stomach extends a thin fold, the 

 gastro-hepatic omentum; and this 



is continued backwards as the duodeno -hepatic omentum connecting 

 the liver with the first portion of the small intestine. 



Vascular system. The heart is enclosed, like that of the Frog, 

 in a thin transparent membrane, the pericardium. It consists of a 

 sinus venosus, right and left auricles, and an incompletely divided 

 ventricle. The sinus vcnosus (Fig. 913, s. v.), into which the large 



FIG. 912. Lacerta agilis. General 

 view of the viscera in their natural 

 relations. Bl. urinary bladder ; Ci. post- 

 caval vein ; ED, rectum ; GB. gall- 

 bladder ; H. heart ; Lg. Lg'. the lungs ; 

 M, stomach ; MD, small intestine ; Oe. 

 oesophagus ; Pn. pancreas* ; 2V, trachea. 

 (After Wiedersheim.) 



