194 An Examination of Weisniannism. 



type in the ascendant. . . . All the lambs produced strikingly resembled 

 each other, and even Englishmen took them for animals of their own 

 country." 



M. Nouel goes on to remark that when this derived breed was 

 bred with itself, the marks of the French breeds were lost. 

 " Some slight traces could be detected by experts, but these 

 soon disappeared." 



Thus we get proof that relatively pure constitutions pre- 

 dominate in progeny over much mixed constitutions. The 

 reason is not difficult to see. Every organism tends to become 

 adapted to its conditions of life ; and all the structures of 

 a species, accustomed through multitudinous generations to the 

 climate, food, and various influences of its locality, are moulded 

 into harmonious co-operation favourable to life in that locality : 

 the result being that in the development of each young indi- 

 vidual, the tendencies conspire to produce the fit organization. 

 It is otherwise when the species is removed to a habitat of 

 different character, or when it is of mixed breed. In the one 

 case its organs, partially out of harmony with the requirements 

 of its new life, become partially out of harmony with one another ; 

 since, while one influence, say of climate, is but little changed, 

 another influence, say of food, is much changed ; and, con- 

 sequently, the perturbed relations of the organs interfere with 

 their original stable equilibrium. Still more in the other case is 

 there a disturbance of equilibrium. In a mongrel the constitu- 

 tion derived from each source repeats itself as far as possible. 

 Hence a conflict of tendencies to evolve two structures more or 

 less unlike. The tendencies do not harmoniously conspire ; 

 but produce partially incongruous sets of organs. And evidently 

 where the breed is one in which there are united the traits of 

 various lines of ancestry, there results an organization so full of 

 small incongruities of structure and action, that it has a much- 

 diminished power of maintaining its balance ; and while it 

 cannot withstand so well adverse influences, it cannot so well 

 hold its own in the offspring. Concerning parents of pure and 

 mixed breeds respectively, severally tending to reproduce their 

 own structures in progeny, we may therefore say, figuratively, 

 that the house divided against itself cannot withstand the house 

 of which the members are in concord. 



