THE URINARY SYSTEM. 155 



dilated into a much-branched glandular enlargement, the 

 vesicula seminalis. 



5. The Vasa Efferentia. 



In both sexes at an early stage, as the Malpighian bodies 

 are forming in the Wolffian body, those nearest to the genital 

 ridges give off tubular branches from their capsules into the 

 ridges. 



In the female frog these tubules are said to expand very 

 greatly, and to give rise to the chambers or cavities present in 

 the adult ovary : but the point is not established with certainty. 



In the male frog these tubules become the vasa efferentia : 

 they become connected with the spermatic tubules, and, as at 

 their other ends they open into the Wolffian tubules, they form 

 passages along which the spermatozoa can get from the testis 

 to the Wolffian duct or ureter, and so out. 



