Cotylogaster occidentalis n. sp. 619 



C. occidentalis Niokkuson 181J'J. 

 In iiitestine of Aplodinotus grunniens (Minnesota River at Jordan). 



4. Genus: Cottjlaspis Leidy 1857. 

 Literature : Kelly '99. — Kofoid '99. — Leidy '57 ; 58. — Monticklli 



'92. _ OSBORN '98. — POIRIER '86. 



Anterior part of body in the form of a truncated cone set 

 obliquely upon an expanded posterior portion which has a convex 

 dorsal and flattened ventral surface. Body not extending beyond the 

 hinder margin of the ventral shield, which is ^/g the length of the 

 animal and composed of 3 longitudinal rows of alveoli. Sense organs 

 present (?). Mouth subterminal, pharynx medium, intestine simple, 

 tubulär, ^/g the length of the body. Genital pore median in front of 

 anterior margin of ventral shield. Testis Single in posterior portion 

 of body. Ovary on right side, smaller than testis. Uterus only 

 moderately elongated, ova not numerous, large, oval. Vitellaria con- 

 sisting of numerous follicles laterally placed. Penis present. 



Live as parasites in mantle cavity of Unionidae and in intestine 

 of turtles. 



The species are: 



C. insignis Leidy 1857. 

 In mantle cavity of various species of Unionidae in N. America. 



C. lenoiri Poir. 1886. 

 In intestine of Tetrathyra from Senegal. 



5. Genus: AsiHdogaster v. Baer 1827. 



Literature : v. Baer '27. — Diesing '34. — Kelly '99. — Kofoid '99. 

 — Macdonald '78. — Stafford '96. — Voeltzkow '88; 88a. 



Body raore or less elongated, broader in the middle narrowing 

 anteriorly to the cylindrical neck, pointed posteriorly. Dorsal surface 

 convex. Ventral shield elliptical covering ^/g or more of the ventral 

 surface. Composed of four rov^^s of rectangular or hexagonal alveoli; 

 margin notched, containing sense organs and in one case provided 

 with retactile tentacles. Mouth terminal, highly distensible. Pharynx 

 usually small. Intestine nearly as long as the body, simple, broaden- 

 ing slightly posteriorly. Sexual aperture median, ventral at base of 

 depression immediately in front of the margin of the ventral sucker. 

 Ovary small; testis Single equal in size to ovary. Vitellary glands 

 numerous, laterally placed. Uterus of medium length, ova rather large 

 elliptical. 



