SCIENCE AND ART OF BREEDING. 107 



able to use as the basis of improvement. The foi:ce of in- 

 heritance, however, is the main point for the breeder to con 

 sider and turn to his advantage, and it is not to be over- 

 looked in the study of this important part of this subject. As 

 has been remarked by Mr.. Darwin: "It is hardly possible, 

 within moderate bounds, to impress on those who have not 

 fully studied this subject, the full conviction and impression 

 of the force of inheritance, which is slowly but surely ac- 

 quired by rearing animals by the study of the various treat- 

 ises which have been published on the subject of breeding 

 of our domestic animals, or by conversation with experi- 

 enced breeders." 



But in thrs regard we must give due force to that pe- 

 culiarity existing in all animals, \vhich is known as atavism, 

 or going back, and by which, after all the work of a breeder, 

 will tend to interfere with his reasonable expectations by the 

 appearance of long back inherited peculiarities by which 

 new difficulties are thrown in the way of expected progress. 

 And not only are forms and dispositions thus inherited from 

 ancestors, long back removed, but the work of the breeder 

 is still further complicated by the reappearance of undesira- 

 ble points which have been thought to have been bred out 

 And, again, the strangest irregularities are thus produced 

 not only by inheritance, but by accidental peculiarities which 

 arise through the action of unexpected events on the nervous 

 system of the female animal. For as Jacob produced streaked 

 and spotted progeny from his sheep and goats, by the use 

 of peeled willow r branches, and as we read the sheep were 

 streaked and spotted, and had bro\vn faces, in consequence 

 of the effect of these unusual appearances placed before 

 them at the coupling time, so similar effects may be pro- 

 duced by w r e know not what accidents, to divert the ex- 

 pectations and purposes of the breeder. We know the very 

 great strength of inherited tendency to diseases, and how the 

 produce of unsound animals, even to the distortion of the 

 joints and limbs, is likely to be affected in a similar way. 

 Thus both for good or ill, the breeder must take into account 

 these natural transmissions of defects or inherited peculiar- 

 ities, and be prepared to meet them, and suffer disappoint- 

 ments and delays, unless by the severest scrutiny he avoids 

 all these risks. Indeed these conditions may be accepted as 



