Terrestrial Pianarians from Japajiese Territories. 



15 



The common genital opening leads into the wide, annularly 

 outbulged vestibukim which is provided with a wall composed of a 

 ciliated epithelium and a muscular coating, thickest on the dorsal 

 side. 



The vas deferens, filled up with spermatozoa, pi'oceeds back- 

 wards and at the sides of the penis makes an abrupt forward bend, 

 to enter the base of the penis and to unite with its fellow of the 

 opposite side into a short common duct which joins the seminal 

 vesicle. 



Text fig. 6. Diagrauimatic genital organs of B. ochroleucum in sagittal section. 

 Index letters as in text figs. 1 and 3. 



The penis consists of the spherical bulbous part of muscular 

 nature and the conical intromittent part lying horizontally in its 

 sheath. The bulb encloses a relatively narrow seminal vesicle witli 

 its smooth wall, which posteriorly narrows gradually into the 

 ejaculatory duct, opening at the tip of the penis. The penis-sheath 

 opens, through the ciliated tubular passage, at the tip of a small 

 conical and downwardly directed process projecting into the ves- 

 tibulum. 



