ATKINS THE SALMON AND ITS AETIFICIAL CULTURE. 331 



or 20 the adult salmon taken with the fly in that river exceed the grilse 

 in the ratio of 10 to 1, or more. 



In our rivers grilse are seldom seen. Three or four per year is the 

 number caught in a weir in the Saint Croix, which takes about 70 

 adults.* In the Denny's the ration of grilse to salmon caught is not 

 more than one to oOO.t In the Penobscot they are quite as rare, many 

 a man having grown old in the salmon-fishery without seeing a single 

 specimen.| Adult salmon running in this river several weeks earlier 

 than in those of Eastern Xew Brunswick, we should naturally expect 

 the advent of grilse early in July in considerable numbers ; but some 

 of the weirs are often kept in operation until the middle or last of July, 

 and sometimes even through Angust, when they take menhaden ; but 

 no grilse enter them. During the latter part of the summer the water 

 at the several falls between Bangor and Oldtown is generally at a low 

 stage, and the attempt of grilse, even in small numbers, to ascend the 

 river, could hardly fail to be frequently detected. A similar state of 

 things exists in the Kennebec. There is no escaping the conclusion 

 that the great run of grilse, which is so prominent a feature in the his- 

 tory of the salmon of the northern rivers, is almost entirely wanting in 

 the rivers of the United States.§ It by no means follows from this that 

 our salmon do not pass through the same phases of growth, or that the 

 growth is more rapid ; but merely that when in the grilse stage they 

 generally lack the instinct that impels their more northern relatives to 

 seek fresh water. 



Of the characteristics of grilse, as ascertained in the rivers they fre- 

 quent, it will be sufficient to say that they exhibit to a great degree the 

 characteristics of the adult j that the main external diflfeiences are, a 

 shorter head, slenderer form, and a difference in the color and mark- 

 ings; that they are remarkably active and agile, leaping to great 

 heights ; that the m.ale is sexually well developed and mates with the 

 adult, but that the female is immature ; and that, like the adult, they 

 abstain from food and consequently lose flesh during their stay in fresh 

 water. 



Of the length of the interval between grilse-hood and maturity our 

 rivers aflbrd no data for an estimate; and we must therefore be con- 

 tent with the supposition that it is nearly the same as in the case of 

 Scottish salmon, and that this year's grilse is next year's adult salmon. 

 If we also accept the Scottish conclusions as to the rate of growth of 

 parr and smolts, we must assign to the growth from the egg to maturity, 

 a period of two or three years. This must, however, await further ob- 

 servations. 



* Letter of L. Wilson. 



t Letter of B. Lincoln, esq. 



t One old li.sbermau says that at Veagie lie has caught, in a dip-net, salmon only a 

 foot long, with hooks on their jaws. Such instances are certainly rare. 



$ Dr. Gilpiu has called my attention to the statemenc by Coach in " British Fishes,", 

 that grilse do not frequent the rivers of Cornwall or, for the most part, those of Devon. 



