327] XORTH AMERICAX ASPIDOGASTRIDAE—STCXKARD 47 



ASPIDOGASTRIDAE 



Because of its peculiar multiloculate adhesive apparatus, Burnieister 

 (1856) called attention to the difference between the genus Aspidogaster 

 and the remainder of the trematodes, and suggested a division of the 

 Trematoda into (1) Malacobothrii for the distomes and holostomes, 

 (2) Pectobothrii for the polystomes, and (3) Aspidobothrii for Aspido- 

 gaster. Subsequent writers however continued to include Aspidogaster 

 with the polystomes until Monticelli (1892) revived the classification 

 of Burmeister, but named the three suborders into which he divided the 

 trematodes, Heterocotylea, Aspidocotylea, and Malacocotylea. 



In the classification of Monticelli, the Aspidocotylea contained the 

 single family Aspidobothridae. Poche (1907) proposed to make the 

 name of the family agree with the rules of zoological nomenclature 

 according to which "The name of the family is formed by adding the 

 ending -idae to the stem of the name of its type genus." Thus the name 

 of the family must become Aspidogastridae. 



The family is of special interest to students of trematocle mor- 

 phology. The form of the adhesive apparatus, with its retractile mar- 

 ginal organs, the separation of the body into dorsal and ventral portions 

 by a muscular partition, the sac-like alimentary tract, and the details 

 of the genital organs are peculiar to the group. The family contains 

 both ectoparasitic and endoparasitic species, forms with direct develop- 

 ment and at least one species which has an intermediate host, while the 

 hosts infested by the adult parasites include both invertebrates and 

 vertebrates, species having been reported from molluscs, fishes, and 

 turtles. 



Summaries or revisions of the group have been made by Diesing 

 (1850, 1859), Taschenberg (1879), Hoyle (1888), Monticelli (1892), 

 Braun (1879-1893), and Nickerson (1902). 



Only three species representing two genera of the family are known 

 from North America, Aspidogaster conchicola von Baer 1827, Cotylaspis 

 insignis Leidy 1856, and Cotylaspis cokeri Barker and Parsons 1914. 

 Representatives of each of these species were available for the present 

 study. The first two species are well known; concerning A. conchicola 

 no further data were obtained, but a few corrections are made to former 

 descriptions of C. insignis. 



