Amcrlcdii FisJtrries Socicii/. 119 



are destroyed l)y the iiieleiiiciieies of the weather or their natural 

 enemies. 



The markings of tlie individuals of the same sex in most 

 species do not vary under the same environment in the wild 

 state. It is claimed that a dozen quail of the same sex taken 

 from as many different localities in the United Stales would 

 show little or no variation in tlie markings of tlieir ]»lumage; 

 and tlie species does not ])erce]itihly vary in size at maturity. It 

 is probable that if a single pair of strong vigorous quail were 

 again released as in the time of Xoah and were to multiply and 

 their progeny live tlirough ct'nturies in fields constantly rich 

 with food, yet so surrounded with natural enemies and subject to 

 such conditions as would tend to cut off the weaklings of the 

 progeny, they would increase in size as a species; and notwith- 

 standing inbreeding would be perpetuated indefinitely. 1 f the 

 food supply was insufficient doubtless the species would decline 

 in size. If no conditions prevailed to cut off the weaklings and 

 inbreeding occurred for any extended period, the species woidd 

 dwindle away. 



Nature's laws provide for the indefinite existence of the spe- 

 cies and the environment largely dt'termiues its })hysical charac- 

 teristics. 



The l)reeder of domestic animals and fowl conforms to 

 Nature's laws by permitting oidy the largest, strongest and most 

 vigorous of his flock to reproduce. He fixes the environment in 

 such manner that the desired size is insured and thus maintains 

 or increases their size as a whole or a species from generation to 

 generation. He may inbreed closely for many .years, perhaps in- 

 definitely, yet by careful selection not impair the size or vigor of 

 the individuals of his flock; but on the conti-ary most certainly 

 add to their Ijeauty and their usefulness. In like manner, the 

 fish culturist can in my opinion, l)y careful selection of his l)reed- 

 ing stock ])r()duce a fish of uniform markings, of larger size, of 

 increased vigor and grt'ater beauty anil usefulness. 



I have no doubt but many practical men will regard as vision- 

 ary and im])ractical the theories here advanced when a]ii)lied to 

 fish culture in ])onds; but with some knowledge of hivcding of 

 domestic animals, after eleven yi'ars of service at a trout hatchery 

 and much of this time given to the practical workings thereof. 



