URINOGENITAL ORGANS 



361 



open into a longitudinal canal from which ducts pass into the 

 kidney, the duct of which therefore serves as a urinogenital duct 

 (Fig. 287). The latter dilates before uniting with its fellow to 

 open into the urinogenital sinus. A somewhat similar arrange- 

 ' ment appears to occur in the male Sturgeon, in which representatives 

 of the oviducts of the female are present in the form of short coelomic 

 funnels opening into the kidney-ducts. It is probable that the other 

 male Ganoids also resemble Lepidosteus in the structure of their 

 urinogenital organs, which, however, require further investigation. 

 In the Dipnoi (Fig. 288) the elongated gonads are invested 



ozfd." 



to 



ofd. 



u-S/ap 



Fig. 286. Fig. 287. 



Fig. 286.— Female UkinogeiNital Organs of A, Lepidosteus, and B, Amia. 

 (A, after Balfour and Parker ; B, after Huxley. ) 

 «, degenerate anterior portion of kidney ; W, bladder ; W, kidney ; o,;l , oviduct ; 

 oihV, aperture of oviduct into bladder ; ovit, peritoneal aperture ; onj, ovary ; 

 p, peritoneum ; u.y. ap, urinogenital aperture; «r, kidney duct. 

 Fig. 287.— Male Urkn-ogbnital Organs of Lepidosteus. (After Balfour and 



Parker. ) 

 hi, bladder ; !.<•, longitudinal canal ; U, testis ; «.(/, ap, urinogenital aperture ; «;■, 

 kidney duct ; w.c/, vasa efferentia. 



