No. 5.] THE MALE OF PERIPATUS EISENII. 



257 



ductive organs are much more complicated than those of the 



female. The latter has two fused ovaries, paired receptacula 



ovorum, paired receptacula semines, and paired uteri. The 



testes are large tubular 



organs beginning at 



about the posterior 



third of the .body and 



running backward 



without much twisting 



to the seminal vesicles, 



which are somewhat 



larger in diameter. 



The seminal vesicles 



appear as dilatations 



of the testes, the right 



one of which is some 



distance in front of the 



left. The vesicles of 



all the specimens I 



have examined are full 



of the spermatogonia 



discharged from the 



testes, spermatocytes, r> i 



and spermatozoa. The 



material was collected 



in October, when the 



R 



FIG. 8. 



testes were active. 

 The seminal vesicles 

 lead posteriorly into a 



pair of exceedingly convoluted vasa deferentia, the right one 

 of which passes over and then under the nerve to join the 

 left, which passes under the nerve. They then run forward 

 side by side, as two small, very thin-walled, straight ducts, for 

 some distance, till they unite to form a common duct. These 

 paired portions of the vasa deferentia are quite full of sperma- 

 tozoa. The unpaired portion of the testicular ducts is of great 

 length, sometimes exceeding twice the length of the whole 

 body. This tube is clearly divided into two portions, the first 



