AMERICAN INSTITUTE. 497 



says, that attempts made in England to improve horses by means 

 of Arabian stallions, have been more successful with mares be- 

 longing to no particular race, than with such as do belong to a race. 

 He illustrates the principle by a case which occurred to him- 

 self. He supposed that he would more speedily obtain fine wool 

 by crossing Roussillon sheep with Merino rams, than by uniting 

 the Aveyron breed with the same rams; but he was disappointed. 

 The Roussillon race being no doubt more ancient, and possessed of 

 greater potency than the Aveyron race, offered greater resistance 

 than the latter to the influence of the Merinos; and after twenty- 

 five years of successive crossing, the primitive characters of the 

 Roussillons still appeared, while the crosses of the Aveyron race 

 after the same length of time, could not be distinguished from 

 the Spanish sheep. Proving, that characters long established 

 through many successive generations, give to a race a fixed type. 

 Now if Monsieur Geron had separated these animals even fifty 

 miles apart, for a few years, and then brought them together, or 

 their progeny, he would have accomplished his object imme- 

 diately. But breeding in the same district, and on the same 

 pastures, the persistency and individuality of the different species, 

 as well as their constitutional tendencies, change, without giving 

 preponderance to either one or the other. Bakewell bred in and 

 in for a number of years, and produced the most brilliant results; 

 his animals were unequalled for early maturity and tendency to 

 fatten, qualities which every stock breeder esteems. They like- 

 wise became almost perfect in symmetry; and in 1789 he received 

 twelve hundred guineas for one year's hire of three bucks brought 

 at a birth. I now have a herd producing in some instances six 

 lambs at a birth, and I cannot obtain more than five hundred 

 dollars per pair. Times have changed since BakewelPs day. 

 Experience taught Bakewell, that when his herd had become so 

 far perfected as to show a great tendency to acquire flesh and 

 arrive at maturity early in life, their original enduring constitu- 

 tions manifested signs of degeneracy. This was the period at 

 which he should have placed a portion of his herd or flocks upon 

 different soils, producing crops containing different proportions of 

 chemical ingredients, change of climate, &c. The animal eco- 

 [Am. Inst.] 32 



