260 



COMPARATIVE ANATOMY. 



B 



DI:D 



RF 



C 



Fn;. 213. ABDOMINAL I'OKKS or VAKIOVS VF.KTKBKATKS. (A, C}-clostome ; 

 B, Elasraobranch ; C, Protopterus ; D, Spatularia.) 



A, anus ; Pa, /X PC, abdominal pores ; Pp, papilla ; AT, cloacal pockets ; UG and 

 ,/, urinogeniiid apertures ; L, L, lip-like margin of cloaral aperture; <'/;, 

 cloaca ; DED, longitudinal folds of the rectum, which end sharply at /,'/': 

 i. point at which the n-ctal gland opens; /;/', pelvic fin; ft, claspers. The 

 arrow in A points towards the he. id, and all the figures are placed similarly to A. 

 In Fig. G, 67 indicates the blind sac of the cloaca, the dorsal wall of which is 

 visihle at D II' ; t, the unpaired apeitnre of the generative ducts ; ED, ED\ 

 the rectum, cut open. The arrow indicates the aperture of the ureters. 



