SELECTION OF BREEDERS. 89 



of an autumn appearance of fungus, are chiefly conspicuous by 

 their absence. 



S. FONTINALIS AS BREEDERS. 



Fontinalis require much more attention when kept for breed- 

 ing purposes than either S. levenensis or S.fario. They are greedy 

 feeders, and very susceptible, especially if in gross habit, to changes 

 of temperature. Fungus does not grow so luxuriantly on their 

 skins as on the skins of English salmon or trout, but it grows 

 there all the same, and is none the less fatal because it is composed 

 of shorter and silkier spores. An east wind in spring, when fon- 

 tinalis are often in high condition for they come into season much 

 earlier than trout in the same water often causes fontinalis to 

 break out in blotches, which speedily become covered with fungus. 

 Dissection discloses considerable inflammation in the lower portion 

 of the gut, extending forwards. If such a thing were known 

 amongst fish, I should be inclined to think it a form of gastric 

 fever. If, on the other hand, fontinalis are under-fed, the yield of 

 ova is very much reduced. But with a moderate allowance of food 

 in spring and autumn, they may be fattened in summer and 

 starved in winter without risk ; but only where they are confined 

 in water over 8 feet deep. Two-year-old fontinalis yield small 

 eggs ; there is not much difference between the size of eggs of 

 three- and four-year-old. At four, fontinalis appear to be thoroughly 

 mature. Those that have been bred for several generations at 

 Howietoun are easier managed than those from imported ova. 

 They interbreed freely with British char, and the cross is fertile. 



SELECTION OF BREEDERS. 



From the foregoing it will be seen that artificial cultivation, 

 by careful selection of mature spawners, improves any particular 

 variety of trout within itself; but it is highly probable, by mix- 

 ing a strain of some other well-chosen variety better and per- 

 manent results may be attained, and in time many well-marked 

 artificial crosses will be bred, each true to a type most suited to 

 the class of water it is intended to stock. Nor need this take 



