“ In central Europe, in the British islands and in the greater part of Scandinavia it is confined to mountain lakes, but farther to the north, in both the Old World and the New, it lives in the sea and ascends rivers to spawn. In Lapland, Iceland, Greenland and other parts of the arctic regions, it ranks among the commonest fishes. ”

“ Sea-run individuals are often nearly plain bright silvery. It is a small species, growing to about 18 in. abundant in all clear, cold streams of North America, east of the Mississippi, northward to Labrador. The fish has been introduced into other parts of the United States, and also into Europe. ”

“ The body is very elongate and covered with extremely small scales. The colour varies from grey to black, with numerous round pale spots, which may be tinged with reddish; the dorsal and caudal fins reticulate with darker. ”