VIGOR AND PREPOTENCY GOVERN 199 



sheep were observed, the first lambs were largely males. 

 As the yeaning season progressed, the number of male 

 and of female lambs were about equal, while at the close 

 of the lambing season the female lambs greatly predomi- 

 nated. In my own experience with five hundred Ameri- 

 can Merino ewes, I found that about nine -tenths of the 

 first quarter of the total crop of lambs were males. 

 Then the sexes began to even up, while, in almost every 

 case, the last quarter of the lambs dropped were largely 

 females. Where large flocks of sheep are kept, it is 

 usual to separate the rams from the flock for three 

 or four months preceding the rutting period. They are 

 fed liberally with such foods as experience has shown 

 will produce unusual vigor. At the same time the ewes 

 are kept under normal conditions or those somewhat less 

 productive of vigor, since the flock is usually large and 

 the pasturage and food somewhat limited. It is evident 

 that under these circumstances the males, when first 

 turned into the flock, will be more vigorous than the 

 females. As the season advances, there being but few 

 of the males, they become depleted in vigor so far as to 

 fall below the vigor of the ewes. Many instances of like 

 experience with flocks of sheep could be cited. 



My friend who owns an island off the coast of South 

 Carolina which is stocked with cattle and swine that 

 roam at will, with no care from the owners, states that 

 they show marked sex -variations in different seasons. 

 After a hard winter and scarcity of food, male pigs 

 predominated. As they were hunted for food during 

 encampment on the island, it was seldom that a female 

 pig could be secured. The males, not being depleted by 



