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have good breeding grounds in tolerably clear water, I apprehend 

 there will be no difficulty from the amount of soil held in suspension 

 in the lower part of the river. The fry will remain in the clear water, 

 if that suits them better, until they are prepared to migrate to the 

 sea. If Congress should favor the memorial that we propose to make, 

 and grant an appropriation for fish culture, the experiment of plant- 

 ing shad in western waters can be tried the coming season. It will 

 cost but little, in any event, and if it succeed, it will give cheap fish 

 to all our western States and territories, and supply one of their 

 greatest wants. 



SPAWNING RACES FOE BROOK TROUT 



Read at the annual meeting of the American Fish Culturists' Association, February, 

 1872, by A. S. Collins. 



All spawning races now in use may be divided into two classes. 

 The first used for getting fish in a ripe state for tlie purpose of obtain- 

 ing and im])regnating the eggs artificially, and the second used for 

 obtaining the impregnated eggs as laid by the fish. Tlie races of the 

 first class for artificial spawning are simple in construction. They 

 should be made about four -feet wide, not less than thirty feet long, 

 and the depth of the water over the gravel varying, with the size of 

 the fish, from six to twelve inches. (As I am speaking to practical 

 fish-breeders I do not enter into details, which they will all under- 

 stand.) There being no gravel in the ponds, the fish will enter into 

 these races during the spawning season only when ripe or nearly ripe. 

 The eggs can be easily taken from nearly every fish pond at any time 

 in these races. They can be impregnated, and will make as good and 

 healthy fish as if laid by the trout themeselves. No moderate pres- 

 sure will force the eggs from a fish unripe or even nearly ripe. 



The races of the second class, or those used for obtaining the natur- 

 ally impregnated eggs of fish, are of much more complex construction. 

 These races are of two kinds. In the first the eggs are left to hatch 

 naturally, the fish being excluded at the end of the spawning season. 

 The simplest form of these is made by screening off" the upper part of 

 a spring brook, allowing the trout free access to it during the spawn- 

 ing season, and driving them all to the lower part of the stream as 

 soon HS the season is closed. The eggs above have then a chance to 

 hatch, and the young fish to develop, the screen being made fine 

 enough to prevent the young fish from passing through. This arrange- 

 ment seems to be very simple, Init is rather difficult to put in practice 

 for several reasons. It is hard to get the screen down so that the 



