10 KENDALL: NEW ENGLAND SALMONS. 



If the cranial character described by Regan (1914, p. 407) characterizes the Pacific 

 salmonids as a distinct group from the Atlantic, and Oncorhynchus is recognized as a 

 valid genus, then the western trouts now regarded as belonging to the genus Salmo 

 unfortunately should have a new name. This the present writer has not the temerity 

 to bestow, as it would serve no purpose of convenience of classification. 



As pertains to New England, the only indigenous genera are Salmo and Salvelinus. 

 The latter constitutes the subject of Part 1 of this memoir. The genus Salmo as at 

 present recognized includes only two native species, and the question of their distinct- 

 ness or identity has been one of long dispute and varied and varying opinion. However, 

 several other species of Salmo and three of Oncorhynchus have been introduced with 

 more or less success so far as their establishment is concerned.^ 



Geographical Distribution of Genera. 



The salmon family occupies the waters of the northern portion of the northern hemi- 

 sphere, practically restricted to coastwise, and inland fresh waters of the great con- 

 tinents and neighboring islands. Thus geographically there are three oceanic and two 

 continental realms. As relates to oceans, each continental area has a common arctic 

 and an eastern and western division. The common, arctic division is occupied by 

 marine, anadromous chars, almost exclusively, but to some extent the influence of warm, 

 oceanic currents has permitted local invasions by other forms, so that salmon and sea 

 trout occur on the Murman coast and in the White Sea. In the western Atlantic there 

 are no 'sea trout.' The northern limit of the salmon is not positively known. 



As regards the fresh-water species of Salmonidse, the contmental areas are subject 

 to more or less subdivision by barriers, of one kind or another, preventing intercom- 

 munication. In the circumboreal or common arctic realm Salvelinus is predominant. 

 In the eastern Pacific are Salvelinus, Oncorhynchus, and 'Salmo.' In the western Pacific, 

 in addition to the foregoing, is Hucho. In the eastern Atlantic are Salvelinus, Salmo, 

 and Hucho (ultra-Mediterranean). In the western Atlantic are Salvelinus and Salmo 

 only. In local, fresh waters of Siberia, where Salvelinus, Hucho, and the Uttle-known and 

 doubtful genus Brachymystax occur, no species of Salmo are recorded excepting in the 

 Bering Sea and Pacific dramages. 



The northern and southern hmits of geographical distribution of aU of the nominal 

 species or forms of each genus are not definitely determined. The most northern records 

 for any salmonoid are 'Floeberg Beach' in north latitude 82° 34' and Cape Sheridan in 

 about the same latitude for one or more species or forms of Salvelinus. The most northern 

 record for Salmo is the White Sea. The most southern Salvelinus is in the moimtains of 

 southern Georgia. The most southern species of Salmo are in the mountain streams of 

 Algeria, Mexico, and Formosa. In both the Atlantic and Pacific regions the chars are 



'The introduced species are: Scotch sea trout (Salmo truita or eroix); brown trout {Salmo fario or S. ausonii or both); 

 Loch Leven trout (Salmo levenesis) ; Swiss lake trout (Salmo lemanus) ; steelhead trout (Salmo gairdnerii or (and) S. irideus) 

 rainbow trout (Salmo shasla); king or chinook salmon (Oncorhynchus Ischawytscha); silver salmon (Oncorhynchus kisutch); 

 humpback salmon (Oncorhynchus gorbuscha). 



