With the females, we have Httle or no trouble from this source, 

 although they are handled and rehandled a great deal more than even 

 the males used for stripping. Once in a while one of the females 

 will get patches of fungus on her head or tail, but as soon as she 

 is relieved of her eggs, the fungus disappears, and the abraded skin 

 rapidly heals over. We always have a surplus of male fish 

 coming on each year, for when the two-year-olds are sorted out 

 to be saved for breeders (as is done each year), the sexes cannot 

 be distinguished and lately the writer has taken to putting out into 

 the lakes all ripe males which it is thought will not be required. 

 This is not good fish culture, for more fish are being carried as 

 breeders than would otherwise be needed; but until some better 

 method of overcoming this trouble is worked out, it is the best that 

 can be done. Our domesticated steelhead breeders are carried year 

 after year without loss from this cause. 



The landlocked salmon is without doubt the most susceptible of 

 any of the Salmonidse to external parasitic disease. This extreme 

 susceptibility is occasioned by the almost entire absence of the usual 

 protective mucous covering, or so-called body slime, which in con- 

 nection with their characteristic habit of resting on the bottom with 

 fins motionless, makes them an easy prey for the millions of patho- 

 genic bacteria and protozoa that lurk in this decaying matter. Their 

 comparatively enormous fins become easily abraded when crowded 

 together in narrow quarters, and present a favorable seat for the 

 origin of parasitic troubles. Most of these external diseases re- 

 spond readily to treatment with gasoline or potassium, and if taken 

 in time seldom reach a serious stage. 



With the first, second, and third generations of our domesti- 

 cated salmon, we experienced a great deal of trouble from thyroid 

 tumor. In the second generation especially, as high as 15 per cent 

 developed this growth in the years they were retained. These fish 

 were all destroyed as soon as the trouble was discovered, and no 

 eggs or milt was ever taken from a fish so affected. For the past 

 six years there has not been found a single fish, either among the 

 breeders or the thousands of two-year-olds planted, that had the 

 least indication of this disease. 



Space will not be taken in this paper for an explanation of the 

 rearing methods, water temperatures, foods, tank sizes, and depths 

 found best suited to the propagation of this fish. It is hoped to give 

 details regarding these matters at some later time. 



All our salmon and steelhead trout are reared to the beginning 

 of the smolt period before they are turned out into the lakes. If 



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