194 



THE FROG 



urinogenital duct. On the outer side of the ureter, and com- 

 municating with it by numerous short ducts, is a glandular 

 body, the seminal vesicle (Figs. 3 and 7, vs. .$;//), which serves 

 to store up the spermatic fluid. 



The spermary itself contains a narrow, irregular, central 

 cavity, from which the efferent ducts proceed and into 

 which open a number of short tubes or crypts (Fig. 62, A). 



FIG. 61. Spermary and kidney of frog showing the relations of the efferent ducts 



(sem id i agr am mat ic). 



C. transverse tubes in kidney ; Ho. spermary ; L. longitudinal tube ; N. kidney ; 

 q. efferent ducts of spermary ; Ur. ureter (urinogenital duct). (From Wieder- 

 sheim's Comp. Anatomy.) 



These are lined with epithelium (f.e), the cells of which 

 divide and subdivide, forming groups of smaller cells. Each 

 of the latter undergoes a remarkable change, becoming con- 

 verted into a rod-like body, produced into a long thread, 

 which performs lashing movements, very much like those of 

 the cilia in ciliated epithelium. These bodies are called 

 sperms or spermatozoa (Fig. 62, A, sp, and B) ; in spite of 



