5150 



pulex) by Haiiiunn UbSS, pp. T-fj and von Linstuw ilSD^A. p. 

 338); and in oop^'jiods (Cyclops agails and C. pulohel'.us by 

 Miazek 1891). 



Thus, ehickeus are kuowu lo. become iutec'ed with 

 one tapeworiu iluougb eaiiujf slugs (Limax). They are 

 supjioseii 10 become inl'ecled with a second through 

 eating suails (Helix); by a third through eaiiug Hies, 

 and by a fourth through eating earthworms. 



Ducks are Icnown to become infected with tw(lworlll^ 

 ilirough swallowing fresh-water crustaceans, and are 

 supposed to become infected with three other tajte 

 worms in the same way; another tapeworm is supptised 

 lo be transmitted to them through tiies. 



Ueese are supposed to become infected with tivi- 

 species of tapeworms by swallowing small fresh water 

 crustaceans. 



Nothing is known in regard to the source of infec 

 lion of the tapeworms of pigeons and turkeys, but in 

 vestigations in this tield should be based upon the ta|>e 

 worms cf chickens. 



THK RELATION OF THK TAPEWORMS OF WILP BIROS 

 TO THOSE OF THE DOMESTICATED FOWLS 



Only two of the chicken tapewonns (Dr. infundibuli 

 formis and T. malleus) have as yet heen recorded for 

 wild birds, but the majority of the tapeworms found 

 ill the doiiusticated ducks and geese are also recorded 

 from closely allied wild birds; besides these forms, 

 however, many species have been described in wild 

 birds which are not known to occur in the domesti 

 cated fowls. (See chart at end of text.1 This renders 

 the economic side of the question of avian cestodes ex 

 tremely ci.ni)iliia1ed and d.-mands a thorough study of 



