URINOGENITAL ORGANS. 



295 



end of the kidney and joining the mesonephric duct (Leydig's duct). The 

 latter is continued forwards beyond 

 the kidney ending blindly in front ; 

 and receiving a small testicular net- 

 work which passes from the testis 

 round the front end of the kidney 

 and is entirely disconnected from the 

 kidney. This would appear to be 

 an extreme modification of the con- 

 dition characteristic of Urodeles, the 

 sexual part of the kidney having been 

 entirely aborted. 



In the Anura nephrostomes are 

 present, but it is doubtful whether they 

 open into the kidney tubules in the 

 adult. It has been asserted * that 

 they open into the renal veins. This 

 statement must be accepted with 

 caution. It appears more probable 

 that they have lost their connection 

 with the renal tubules and persist as 

 ciliated cups on the surface of the 

 kidney. 



Bidder's organ is foimd in Bufo a? a structure attached to the front end 

 of the generative gland. In both sexes it consists of an aggregation' of 

 immature ova. 



The fat-body consists of lymphatic tissue with fat in the meshes. It 

 appears to be a reserve of nutriment which is dra^wn upon when the sexual 

 glands are becoming mature. 



■Uf 



Fig. 166. — Uniiogenit il s\sttiii(it male 

 JSu/o (after Spengel)./ fat body; m 

 malpighian body ; ov Bidder's organ 

 (ovary) ; t testis ; iig duct of kidney. 



Fig. 167. — Urinogenital system 

 of Ahftes ohstetrkans (from 

 Gegenbaur, after Spengel). 

 t testis ; ng longitudinal 

 duct of kidney (meso- 

 nephric) ; sb seminal vesicle ; 

 t testis ; u ureter (after 

 Spengel, from Gegenbaur). 



The Suprarenal bodies are small yellow 

 structures on the ventral surface of the 

 kidneys in the Anura, on their median 

 side in Urodela. 



The oviducts open separately into the 

 cloaca, except in Hyla, Bufo and Alytes, 

 in which the opening is median. They 

 receive through their abdominal opening 

 the eggs, which are dehisced into the 

 body-cavity. They are usually more or 

 less convoluted, possess glandular walls 

 which secrete an albuminous covering 

 for the eggs, and they are frequently 

 dilated into a receptacle in which the 

 eggs are collected, close to their cloacaL 

 opening. 



E. J. Bles, Proc. Camhridge Phil. Soc, 9, 1898. 



