AILMENTS AND DISEASES 



FIG. 8 1 Distomum 

 graci/e, a Trematod par- 

 asite. Greatly enlarged. 



FIG. 82 Diphsto- 

 mum cuticolaj a Trema- 

 tod parasite. Greatly 

 enlarged. 



FIG. 83. Gaster- 

 ostoma graciUscensj a 

 Trematod parasite. 

 Greatly enlarged. 



Cestoda or Tapeworms. This group comprises the Tapeworms 

 and other cystic Entozoa which are parasitic during the greater part of 

 their lives; with some species the eggs only are free during certain periods 

 to change their residence. The Cestoda are taken as one group or sub-order, 

 the Pseudophyllida, which consists of five families, the Bothriocephalida, 

 Tetraphylltda, CyclophylUd<£, Diphyllida, and Trypanorhycha; divided into 

 16 sub-families, 72 genera and 28 related genera, parasitic on Vertebrates, 

 of which the following species are found in freshwater fishes and amphibia 

 of the United States : — 



Species 



Host 



Bothriocefhalis proboscideus 



" nodosus 



Cyathocephalus truncatus 

 Dibothrium hastatum 

 ' ' cordiceps 



" infundibuliforme 



Dacnitus globoia 

 Ligula simplkissima 



' ' catostomi 

 Monobothrium hexacotyle 

 ' ' terebrans 



Schistocephalus dimorphus 



" solidus 



Tienia scevelini 

 " ocellata 

 " dilatata 

 Triculpidaria nodulus 



Carp and other Cyprinidae 



Stickleback 



Whitefish 



Sturgeon 



Trout 



Burbot and Whitefish 



Trout 



Carp and Tench 



Sucker and Chub 



Sucker 



" and Chub 

 Sculpin, etc. 



Stickleback and Cyprinids 

 Whitefish 

 Rock Bass 

 Eel 

 Bass, Perch and Pike 



Part Inhabited 



phylorus and intestines 

 alimentary canal 

 phyloris 

 intestine 



body cavity 



intestine, etc. 



abdominal cavity 

 intestine 



c t and muscular 

 tissues 



FIG. 84 Boihriocephalis 

 proboscideuSj a Cestod para- 

 site. Twice natural size. 



FIG. 85 Ligula 

 simp/icissima, a Ces- 

 tod parasite. Nat- 

 ural size of imma- 

 ture form, the adult 

 is parasitic in Mam- 

 mals. 



FIG. 86 Sciis- 

 tocephalus solidus^ a 

 Cestod parasite. 

 Immature form, 6 

 to 1 5 mm. long, the 

 adult is parasitic in 

 Aquatic Birds. 



148 



