No. 603] SHORTER ARTICLES AND DISCUSSION 187 



sturgeon and the lamprey is noted by Professor Meek and in both 

 eases the facts now observed are of long standing. Both had ap- 

 parently "refuge-regions" during glacial times. We do not, how- 

 ever, see the reason for the suggestion that the green sturgeon of 

 California (now almost extinct) "may have been derived from 

 the Atlantic during the post-glacial disturbance." 



The migrations and breeding habits of the herring are treated 

 with special fullness, proportionate to the economic value of the 

 species. For in the north, as Bjornson informs us, wherever a 

 herring school touches the coast a town springs up, like drift- 

 wood on the beach. 



In the account of the trout, very good as a whole, we may note 

 that the genus Salmo is represented by different forms, originally 

 derived from the Pacific coast, in the Great Basin of Utah, and 

 also in the headwaters of the Colorado, Rio Grande, Arkansas 

 and Platte, as well as the Columbia and Missouri. It is probable 

 that the freshwater irideus (Rainbow trout) and the sea-run 

 gairdneri (steelhead) are not really different, but both are quite 

 separate from the cutthroat trout {Salmo clarki, wrongly identi- 

 fied at first by American authors with the Kamchatkan Salmo 

 myhiss) from the Tahoe trout {Salmo henskawi) and from the 

 several local forms which have sprung from these or which have 

 preceded their advent. The last seems to be the case with the 

 silver trout of Lake Tahoe {Salmo regalis). The suggestion of 

 Professor Meek that the European salmon {Salmo salar) of the 

 Miocene was divided into a North Atlantic and a Mediterranean 

 form is interesting. The latter developed as a "trout" dividing 

 into sea trout {Salmo trutta) and burn (or brook) trout {Salmo 

 fario). But these two are as yet not really differentiated, corre- 

 sponding in a way to the rainbows and steelheads of the Pacific 

 coast. Professor Meek says : 



There is thus good reason for believing that the sea trout and the 



and the other confining itself to fresh water. 



Our own experience with the species lends probability to this 



That "the salmon preceded the trouts" in time is also probable, 

 but the western species of trout must have been derived from the 

 trout of Europe and Asia. 



The Pacific salmon must be older and more primitive than the 

 Atlantic salmon, for the six species differ from one another, more 

 than any trout or even the Atlantic salmon itself differs from 

 any other black-spotted trout whatever. 



