FISH CULTURE. ^ 251 



eggs were best, and also tbat eggs liatclied iu a temi^erature of 40° to 

 450 made the hardiest fish. Our experiments thus far seem to indicate 

 that there is no ditlereuce, fish from eggs spawned in March doing as 

 well as those from eggs spawned in October, aud eggs hatched in 50° 

 doing as well as those hatched in 35°. 



Groicing young trout. — This has always been the rock upon which new 

 beginners have been shipwrecked. Yerj- few ])ersons have found any spec- 

 ial difficulty in hatching out the eggs or in keeping the young fish until 

 the sac was entirely absorbed. But a very general want of success has 

 been felt in rearing the brook-trout from the age of forty-five days to 

 the age of three or four months. There must be some reason for this ; 

 let us see if we cannot find it. The failure must lie in one or more of 

 four circumstances. Either the eggs are not good in the first place, 

 that is, imperfectly developed, or for some reason producing weakly fish, 

 or the water in which the experiment is tried is not adapted to the young 

 fish, or the food which is commonly used is not the proper food, or the 

 fault lies in the person feediug them. Now, does the fault lie in the 

 eggs ? TVe have no doubt that fish sometimes, from a lack of vitality, 

 &c., produce imperfect eggs, and we have just as little doubt that 

 the greater part of such eggs die before they are many weeks old. A 

 few may survive the hatching process and absorption of the sac, but 

 their number is exceedingly small. Our reasons for this belief are as 

 follows : First, we have often taken the eggs from fish evidently 

 diseased, and kept them iu a place separate from others. In nine cases 

 out of ten it was impossible to impregnate these eggs at all, and of 

 those which were impregnated not one-tenth would live until the fish 

 became plainly visible to the naked eye, aud a still less proportion would 

 survive until the sac was absorbed. Then, again, if the failure to raise 

 the young fish lie in the imperfection of the egg, we should expect 

 in every case that some at least of the fish should be vigorous and 

 healthy, as it is hardly possible that all the eggs should be imperfect. 

 Whereas it is the general complaint of those who fail, tliat all their fish 

 die together, and that they can raise none of them ; aud, still further, of 

 two persons receiving eggs from the same batch, one will raise a good 

 percentage and the other will raise none. Therefore it would seem to 

 us that the fault does not lie iu the egg or in any mauiprJatlon thereof. 

 Neither can it be in any large nujuber of cases that the water is unfit 

 for them, because they have been raised by different persons in water 

 at varying degrees of temperature and impregnated more variously 

 with minerals or salts ; and still less can this be true, because successes 

 and ftiilures have been made in different seasons by the same person 

 in the same waters. Neither do we believe that the failure lies in the 

 matter of food, as they have been raised successfully on curd alone, on 

 liver alone, on beef-heart alone, on beefsteak alone, on liver aud curds, 

 on heart aud curds, on liver and sweet cream, and on all together. It 

 therefore looks reasonable to suppose that the failures must be looked 

 for in the person feeding them. Aud this supposition is strengthened 

 by the fact that some persons never fail to raise a crop and others always 

 fail. Let us look at the facts iu the case, and see what common sense 

 will teach. 



Suppose that a man has eggs enough to hatch out ten thousand trout. 

 During the period of sac absorption, if he attends to the flow of water 

 and does not raise it too fast, he will lose but few. When the sac is 

 nearly absorbed, and the trout begin to come to the surface, they must 

 be fed. Now the question is what substance to feed. Suppose our 

 friend thinks, according to prevailing opinion, that curd does not con- 



