NO. 15 ARTHROPOD HOSTS OK HELMINTHS HALL 2"] 



All analysis of the records given shows the following: 



PLAGIORCHIIDAE 



In the Plagiorchiidae we have a group of flukes which have a wide 

 range of intermediate hosts, including the insect groups Odonata, 

 Diptera, Trichoptera, Plecoptera, Ephemerida, and Coleoptera, and 

 the crustacean groups, Decapoda and Amphipoda. This range of 

 intermediate hosts is associated with the range of primary hosts, 

 which include fish, amphibians, and birds. Considered on the basis of 

 primary hosts, the plagiorchids in birds utilize Odonata as inter- 

 mediate hosts, those in fish use the Diptera, Odonata, Trichoptera, 

 Plecoptera and Decapoda ; while those in frogs use the Odonata, Tri- 

 choptera, Coleoptera, Ephemerida, Plecoptera, and Amphipoda. The 

 Trichoptera and the Odonata appear to be the most important inter- 

 mediate hosts. 



LECITHODENDRIIDAE 



In the Lecithodendriidae the insects serve as intermediate hosts and 

 they include the Plecoptera, Ephemerida, Coleoptera, Diptera, Tri- 

 choptera, Odonata and " amphibious insects." The frog flukes of 

 this family use Odonata and Coleoptera as intermediate hosts; the 

 bat flukes use Plecoptera, Ephemerida, Diptera, and Trichoptera. 

 Here also the insects have the double role of intermediate host for the 

 fluke and of food for the primary host. 



OPISTHORCHIIDAE 



In the Opisthorchiidae, insects, specified by Stafford (1927), as 

 amphibious insects, are the only reported hosts. Since this is a large 

 family with a wide range of hosts, little of a general nature could be 

 concluded from the foregoing. 



ALLOCREADIIDAE 



In the Allocreadiidae, parasitic for the most part in fish, the inter- 

 mediate hosts include Ephemerida, Trichoptera, Diptera, and Deca- 

 poda, the more important being the Ephemerida and the Decapoda. 

 The intermediate hosts probably serve as such by virtue of their role 

 as food for fish. The record for Asfacotrema cirrigerum of a bird as 

 primary host is found in a footnote reference based apparently on 

 correspondence and lacks evidence or detail. 



