297] 



PROTEOCEPHALIDAE—LA RUE 



2ff7 



Proteocephalus perplexus 



This species is known at present only from the Illinois River at 

 Havana, 111. Leidy's notice (1886) of Taenia fiZicoUis found in Amia 

 calva from North Carolina may refer to this species. The hosts are 

 Amia calva and Lepisosteus platostomus. The former is common in 

 rivers and lakes of central and southern North America, including lakes 

 Huron and Erie. The latter host, Lepisosteus platostomus, occurs 

 throughout the Mississippi valley but is said to avoid the smaller 

 streams. Thus in the Mississippi valley the two hosts have a common 

 range. Amia feeds on fish, crawfish and molluscs while the other host 

 takes fish almost exclusively. If Lepisosteus includes Amia in its diet 

 it may secure its infection from Amia which may perhaps serve as both 

 primary and secondary host. On account of its armor it is not at all 

 likely that the gar serves as food for Amia. It has seemed rather re- 

 markable that this parasite was not found in Amia calva of the Great 

 Lakes. A most careful examination of the material collected by Pro- 

 fessor Ward in the course of his work on the Great Lakes has shown 

 that it does not exist there. Likewise it seems remarkable that the other 

 carnivorous fish of the Illinois River, such as the bass, do not have this 

 infection. Some of these fish eat very much the same food as Amia. 



