140 BULLETIN OF THE BUREAU OF FISHERIES 



The trout that follow this habit grow so much more rapidly on the abundant rations 

 the salt estuaries provide than do most of their relatives that remain in the brook 

 that sea fish run up to from 1 to 3 pounds in weight in streams where the fresh- 

 water trout seldom exceed half a pound. 



On Cape Cod the sea trout go down to salt water in November immediately 

 after spawning, winter there, and begin to run in again in April, all being once more 

 in brackish or fresh water by mid-May. In the Nova Scotian streams tributary to 

 the Bay of Fundy it is said that they do not appear until later in spring (we can not 

 vouch for this). While in salt water — at least along Cape Cod — the trout feed 

 chiefly on shrimps, mummiohogs (Fundulus), and other small fish. Trout never 

 stray far from the stream mouths in the Gulf. So close, indeed, do they hang that 

 we have never head of the capture of a single one outside the tidal creek or estuary 

 into which its home stream empties. Hence trout have no place 55 in the fish fauna 

 of the open Gulf. 



THE SMELTS. FAMILY ARGENTINID^ 



The smelts are small salmons in all essential respects, except that the stomach 

 is simply a sac with few or no pyloric cceca, whereas in their larger relatives 

 of the salmon family there are large numbers of such cceca. However, it is not 

 necessary to look so deeply among the few species proper to the Gulf to tell if a 

 fish be smelt or very young salmoD, for the former all have pointed noses and are 

 of slender form, whereas the young of our three salt-water salmons — humpback, 

 Atlantic, and sea trout — are stouter bodied with rounded noses. In most cases, 

 too, the shape of the tail alone would suffice to separate smelt from salmon smolt, 

 for in the latter it is never as deeply forked as in the former, though considerably 

 emarginate instead of square as in the adult salmon. 



Three smelt fishes occur in the Gulf of Maine — the smelt (very common), 

 capelin (a sporadic visitor from the north), and argentine (rare, but perhaps occur- 

 ring more regularly than actual recorded captures suggest). 



KEY TO GULF OF MAINE SMELTS 



1. Dorsal fin situated far behind pectorals 2 



Dorsal fin originates over the tip of pectorals - Argentine, p. 147 



2. Upper jaw almost as long as lower; teeth large; there is a group of strong fangs on the 



tongue; pectoral fins have 12 rays or fewer Smelt, p. 143 



Lower jaw much longer than upper; teeth so small as hardly to be visible; no fangs on 

 tongue; pectoral fins have 15 to 20 rays Capelin, p. 140 



49. Capelin (Mallotus villosus Muller) 



Jordan and Evermann, 1896-1900, p. 520. 



Description. — The capelin is an even slenderer fish than the smelt, its body being 

 only about one-seventh to one-eighth as deep and about one-twelfth as thick as 

 long, except in the case of females with the abdomen distended with spawn; it 

 is of nearly uniform depth from gill cover to anal fin, whereas the smelt is usually 

 deepest about its mid length (at least if the fish is fat) , which gives the two species 



M Trout are occasionally taken about Woods Hole in the nets in winter. 



