1910. 



ENTOZOA OF THE HIPPOPOTAMUS. 



245 



parts, the anterior border of the front testis marks the commence- 

 ment of the second portion. The testes are separated from each 

 other by a space equivalent to their antero-posterior diameter. 



The vesicula seminalis is represented by a small rosette-like 

 coil of the genital tube midway between the anterior testis and 

 the bifurcation of the gut. It merges into the pars musculosa, a 

 short feebly developed portion about 015 mm. long. 



The pars prostatica, 0*15 mm. in length, is straight and has a 

 fissure-like cavity. It discharges by the penile ductus ejacula- 

 torius that protrudes into the metraterm. 



The ductus hermaphroditicus, 0*1 mm. in length, projects like 

 the tip of a finger into the atrium for a distance of O03 mm. 



The yolk-glands form two vertical rows around the gut- 

 branches, and range from the bifurcation of the gut to the level 

 of the ovary. 



Text-fig. 32. 



Parampliisbomum minutum. Median longitudinal section. 



The ovary is spheroidal and is placed dorsad of and slightly 

 posterior to the testis. 



The shell-glands lie immediately behind the ovary, resting upon 

 the anterior wall of the excretory vesicle. 



The uterus is filled with eggs and passes into the metraterm 

 0"3 mm. behind the atrium. 



Laurer's canal passes outwards from the level of the shell-glands 

 to open some little distance in front of the excretory pore ; it does 

 not cross any portion of the excretory vesicle or duct. 



The excretory vesicle is small and, as seen in vertical section, 

 has an exceedingly irregular outline. It lies almost wholly in 



