THE SKATE. 



55 



Fig. i8.— Raja batis. The urinogenital organs of the male (one- 

 third nat. size). 



The organs are supposed to be removed from the body along with a 

 small portion of the oesophagus {ixs), and viewed from the ventral aspect : 

 the right testis (i) is removed, along with the corresponding epididymis 

 («/)(/) and all but the posterior extremity of the vas deferens {v.d), 

 which, with the sperm sac (s.s) is turned outwards to display the 

 ureters {ur) : the cloaca (c/), the urinogenital sinus (ug.s), and the 

 right vesicula seminalis (v.s) and sperm sac [s.s) are laid open. 



a.p, abdominal pore : cl, cloaca . epri, epididymis : i.r, inter-renal 

 body : k, kidney : (es, oesophagus : fn.d, pronephric duct : s.s, sperm 

 sac : s.s', its opening into the urinogenital sinus : i, testis : ug.f, urino- 

 genital papilla: ug.s, urinogenital sinus: ur, ureter: u/, its opening 

 into the urinogenital sinus: v.d, vas deferens: v.s, vesicula seminalis : 

 »./, its opening into the sperm sac. 



