DI GENETIC TREMATODES 49 



Host : Castor canadensis Ore. Shaw, 1947 ; Senger & Neil- 



and, 1955 



Morphology: Described and figured by Skrjabin (1949). 



Biology : Cercariae develop in Fossaria parva in Louisiana, encyst on lettuce, and 

 develop experimentally in guinea pigs (Bennett and Humes, 1939). 



Zygocotyle lunatum (Diesing, 1836) Stunkard, 1916 



Synonyms : Amphistoma lunatum Diesing, 1836 

 Zygocotyle ceratosa Stunkard, 1916 

 Chiorchis lunatits Travossos, 1921 

 Cercaria poconensis Wille}', 1930 



Hosts : Olor buccinator B.C. Cowan, 1946 



Anas platyrhynchus Ore. *Exact location unknown 



Additional hosts recorded in Yamaguti (1958). 



Biology : Willey ( 1930, 1941 ) showed that Cercaria poconensis Willey, 1930, de- 

 velops in species of Heliso)iia and develops to maturity in many ducks and 

 some mammals. The lymph vessels are probablj' remnants of the cercaria! 

 excretory vesicle (Willey, 1954). 



Family PHILOPHTHALMIDAE 



Echinostephilla haematopi, Ching, 1960 



Host : Haeniatopus bachmani Wash. Ching 1960a 



Biology: Ching, 1960a, attempted the life history of this species. 



Parorchis acanthus (Nicoll, 1906) Nicoll, 1907 



Synonyms : Zciigorchis acanthus Nicoll, 1906 



Parorchis avitus Linton, 1914 (Cable & Martin, 1935) 



Host : Lams occidentalis Ore. *Lincoln County 



Hosts from the Atlantic have been listed bv Nicoll (1906, 1907b) and Linton 

 (1914). 



Morphology: Described and figured by Dawes (1946) and Skrjabin (1947b). 

 Rees (1939, 1940) elaborated on the morphology, embryology, etc., but 

 Brien (1954) was not in complete agreement with her. Perez Vigueras 

 (1956) redescribed and figured this form. 



Biologi' : The life historj' has been worked out by Lebour (1914), Lebour and 

 Elmhirst (1922), and Stunkard and Cable (1932). Oguri and Chu (1955) 

 worked on the effect of diet on infections of P. acanthus. 



Asterisks denote new (previously unpublished) reports of the parasite in the area. 



