THE LIZARD. 169 



wall of the cloaca, and having a bilobed free anterior 

 extremity or fundus, 



178. The kidneys (Figs. 40 — 42, /5), two dark, reddish- 

 brown bodies, situated between the dorsal wall of the pelvic 

 cavity and the rectum : their anterior ends are about on a 

 level with the corpora adiposa, their posterior ends reach 

 back a little beyond the level of the vent : they are irregular 

 in shape, adapting themselves to the form of the cavity in 

 which they lie, and their tapering posterior ends are closely 

 applied to one another : they are covered by peritoneum on 

 the ventral face only': each consists of two lobes, an anterior 

 and a posterior. 



179. The pelvic veins (Fig. 40, pi) have already been 

 seen (§ 138) attached to the edges of the corpora adiposa : 

 traced backwards, each is seen to pass across the ventral 

 face of the corresponding kidney, and to be united with its 

 fellow to form a single trunk : this latter, which by its 

 bifurcation forms the pelvic veins, is the caudal vein (c) ; 

 it lies along the ventral aspect of the caudal vertebrae and 

 brings back blood from the various tissues of the tail. 



180. The principal renal portal vein, arising from the 

 pelvic vein at the point where it turns outwards across the 

 ventral face of the kidney : it enters the anterior lobe of the 

 kidney, supplying it with venous blood : the posterior lobe 

 is supplied by smaller renal portal veins springing from the 

 hinder part of the pelvic veins. 



181. The femoral {/.v) and sciatic (sc) veins, two 

 trunks, the former from the anterior, the latter from the 

 posterior region of the leg, and opening into the corres- 

 ponding pelvic vein. 



182. The two trunks which by their union form the 

 postcaval vein (§ 173) : the right is considerably the 

 larger and is directly continued into the postcaval, while 



