548 



AMPHIBIA. 



thin-walled and straight, then glandular and coiled, ter- 

 minally thin-walled and dilated. In the median part, the 

 ova are surrounded with jelly ; the terminal uterine parts 

 open on the dorsal wall of the cloaca. In the females the 

 Wolffian ducts act solely as ureters. There are occasional 

 variations in the nature of the reproductive organs, and 

 sometimes the hermaphrodite stage through which the tad- 

 poles pass, is to some extent retained. Attached to the 

 anterior end of the reproductive organs are yellow lobed 



Fig. 183. — Urinogenital sys- 

 tem of Male Frog. (After 

 EcKER.) 



f.l'., Fatty bodies ; z'.r., vena cava ; 

 7'., testis ; A'., kidney; w.d., ^VoIlTian 

 duct ; c/., cloaca ; /-'/., bladder. 



Fig. 1S4. — Urinogenital s)'s- 

 teiii of Female Frog. (After 

 EcKER.) 



oz'd. , Opening of oviduct ; cv., ovary ; 

 f.l'., fatty body; A'., Kidney; Vt., 

 uterus; Ur., opening of ureters into 

 cloaca (c/.) 



" fatty bodies," largest in the males. It has been suggested 

 that they contain stores of reserve material, which is absorbed 

 at certain seasons. They seem to be fatty degenerations of 

 the anterior part of the genital ridges. The head kidney or 



