BLOOD-VASCULAR SYSTEM, ETC., OF AMIURUS CATUS. 443 



does not appeal' to present any peculiarities, and nothing further 

 need be said regarding it. 



THE GENITAL ORGANS. 



I have not studied any details in connection with these organs, and 

 will merely note a few of their general features. They are paired 

 glands, 65 mm. long, lying along the ventral surface of the kidney 

 and posterior part of the air-bladder, and attached by a median con- 

 tinuation of the peritoneum which surrounds them, to the mesentery 

 close to its junction to the peritoneum covering the kidney and air- 

 bladder. 



The ovaries of the female are cylindrical in form, bluntly pointed 

 at both ends. The ova-duct is a large passage in the centre around 

 which the ova are developed from the entire wall, but more abun- 

 dantly along the median side. The ova, seen through the thin trans- 

 parent membrane of the organ, give it a bright yellow color. 



The testes are greyish-white in colox*, flattened in form, with a 

 straight median edge along which the vas deferens lies, while the 

 lateral edge is broken into a great many small lobes. 



The genital ducts join to form a common median duct. In the 

 female this opens on a papilla between the urinary opening and the 

 vent, but in the male it joins the urethra and opens with it on a 

 common uro-genital papilla. 



These papillae, upon which the openings of intestine and the urinary 

 and genital-ducts are situated, ai'ise in a longitudinal median depres- 

 sion, 15 mm. in length and very shallow. The papillae and the sur- 

 rounding depression are remarkable for the richness of their blood 

 supply. 



The above arrangement of the uro-genital ducts is exactly similar 

 to that described by Wiedersheim as most common among the Tele- 

 ostei. 



The blood supply to these organs has already been referred to. The 

 trunk stems run in the median line, giving off, at intervals, lateral 

 branches, which run parallel to one another across the attaching peri- 

 toneum to the glands. The vessels divide into a dorsal and ventral 

 stem which supplies or drains respectively these halves of the organs. 



31 



