80 PKOPEB COLOK OF YOLK. 



COLOB OF YOLK. The external yolk is occasionally 

 somewhat yellowish of the tinge of dirty bees -wax but 

 more generally of some dark shade of brown, or what would 

 more commonly be termed black. The darker color is 

 preferred. All American Merino sheep having what is 

 esteemed a sufficient amount of yolk, become very dark 

 colored each year before the winter is far advanced, if they 

 are housed from summer and winter storms after shearing. 

 Rains wash away the yolk and with it the color. But the yolk 

 is soluble in different degrees in different families, and even on 

 different animals of the same flock. The Paular (Rich) sheep 

 hold their color uncommonly well ; the French rapidly bleach. 

 It has been supposed that the black color is communicated to 

 external yolk by dust, the pollen of hay, etc. These may 

 contribute to the result, but I have recently learned from 

 entirely reliable persons, who house their sheep in summer, 

 that if kept entirely dry, they never assume their darkest 

 color that to obtain this, they must be exposed to dews, 

 light sprinkles of rain, or the contents of the watering pot. 

 The change in color, accordingly, is partly chemical. 



Internal yolk varies in color from a pure white to a deep 

 yellow. It has been rather the fashion, in this country, since 

 the days of the Saxon sheep, to breed for the former, and 

 this is the prevailing color in the American Paulars. The 

 breeders of the American Infantados, and of the Silesians, 

 generally follow the old Spanish custom of giving preference 

 to shades of yellow. A brilliant "golden tinge," faint or 

 imperceptible near the roots of the wool, but deepening 

 towards its outer extremities, is the one sought after. The 

 founder of the improved Infantado family has, as already 

 stated, bred steadily for that color; and he has done so not 

 merely as a matter of taste, but under the impression that it 

 betokens a vigorous growth of wool and general vigor of 

 constitution and particularly vigor of that kind, which 

 exhibits itself in the forcible transmission of individual 

 properties to progeny. But this "golden tinge" is not 

 to be mistaken for the deep saffron yellow which attends 

 cotting or for a dull, dead yellow or for a tawny bees- 

 wax hue or for the hue of "nankeen" cloth, sometimes seen 

 in imperfectly bred animals. The favorite color among the 

 French breeders is a creamy one. In answer to inquiries 

 made by me, in 1862, several experienced manufacturers all 

 I consulted concurred in the statement that the color of the 

 yolk is not, in itself, a matter of any consequence, in reference 



