414 



BULLETIN OF THE BUREAU OF FISHERIES. 



at which, from an adequate examination of material, the disease is definitely known 

 to exist or to have existed in an advanced stage as expressed by the exhibition of visible 

 tumors. 



District of Columbia. 

 Iowa: Manchester. 

 Maine: Craig Brook, Auburn. 

 Michigan: Paris; Northville. 

 Missouri: Neosho. 

 Montana: Bozeman. 

 New Hampshire: Nashua. 

 New York: Bath; Margaret viUe 

 hatcheries. 



and other 



Pennsj'lvania: Spruce Creek; Glen Eyre. 



South Dakota: Spearfish. 



Virginia: Wytheville. 



Vermont: Roxbury; St. Johnsbury. 



Washington: North Yakima. 



West Virginia: White Sulphur Springs. 



NAMES OF SPECIES AND HYBRIDS. 



While the disease primarily and chiefly is found in the brook trout, it has been 

 observed among all the following species and hybrids in the United States. Two of 

 these, the brown trout and Loch Leven trout, are introduced species, and one — the 

 whitefish — belonging to a subfamily of the Salmonidae, is not the subject of fish culture 

 as an adult and is represented by only one specimen bearing a tumor, this being a wild 

 fish from a lake. It is quite certain that this list will be much extended as fast as other 

 species of salmonoids are brought under domestication. The single species which, 

 though bred artificially, can not yet be included among the species subject to thyroid 

 carcinoma, is the sea trout (Salmo truita Linnaeus), introduced into the United States 

 as the Scotch sea trout. 



American brook trout; square-tail trout; redspot trout; 



speckled trout Salvelinus fontinalis (Mitchill). 



Rainbow trout Salmo irideus Gibbons. 



Landlocked salmon; Sebago salmon; Schoodic salmon Salmo sebago Girard. 



Loch Leven trout Salmo levensis Walker. 



Brown trout; von Behr trout Salmo fario Linnteus. 



Atlantic salmon Salmo salar Linnseus. 



Great Lakes trout; lake trout; Mackinaw trout; namaycush 



trout; longe; limge; togue; laker Cristivomer namaycush (Walbaum). 



Humpback salmon Oncorhynchus gorbuscha (Walbaum). 



Common whitefish Coregonus clupeiformis (Mitchill). 



Hybrid salmon: 



Female silver salmon 



Male humpback salmon. . 



Female silver salmon 



Male Chinook salmon 



Female blueback salmon. 

 Male humpback salmon . , 

 Female humpback salmon 

 Male blueback salmon. .. 



Female brook trout 



Male landlocked salmon . . 

 Hybrid trout: 



American brook trout 



American saibling or sunapee trout . 



Oncorh>Tichus kisutch (Walbaum). 

 Oncorhynchus gorbuscha (Walbaum). 

 Oncorhynchus kisutch (Walbaum). 

 Oncorhynchus tschavvytscha (Walbaum). 

 Oncorhj-nchus nerka (Walbaum). 

 Oncorhynchus gorbuscha (Walbaum). 

 Oncorhj-nchus gorbuscha (Walbaum). 

 Oncorhynchus nerka (Walbaum). 

 Salvelinus fontinalis. 

 Salmo sebago. 



(Salvelinus fontinalis. 

 Salvelinus aureolus (Bean). 



