8 1 Psychological Distinctions between Man and Animals, 



scene of existence, whenever that shall happen, will probably 

 be brought about on another principle : how, it would be most 







appears not to have been duly considered by those who have written on the 

 subject. We have every reason to believe that the original germ of an 

 animal may be developed into either male or female ; and it is certain, that 

 external circumstances exercise a very considerable influence in determining 

 the sex of the future being. Now, the results of experiments instituted on 

 sheep by the Agricultural Society of Severac fully warrant the conclusion, 

 that, where species exist under circumstances favourable for their increase, 

 a greater number of that sex is produced, which , in polygamous animals is 

 most effectual for their multiplication ; whereas the contrary obtains, pro- 

 bably, in proportion to the difficulty of obtaining a livelihood. The relative 

 age and constitutional vigour of the parents is likewise an important ele- 

 ment in this problem ; and, combined with the former, will enable us to 

 calculate an average with tolerable precision. I have collected some very 

 curious facts bearing upon this subject, some of which are extremely 

 difficult of explanation. Mr. Knapp, in his Journal of a Naturalist, has the 

 following, which is worthy of close attention : — " The most remarkable in- 

 stance," he observes, of variation in the relative proportion of the sexes, 

 *' that I remember of late, happened in 1825. How far it extended I do 

 not know ; but, for many miles round us, we had in that year scarcely any 

 female calves born. Dairies of forty or fifty cows produced not more than 

 five or six j those of inferior numbers in the same proportion ; and the price 

 of female calves for rearing was greatly augmented. In a wild state," he 

 justly observes, "an event like this would have considerable influence 

 upon the usual product of some future herd." (Note top. 138.) This 

 occurred in Gloucestershire. The character of the preceding season is not 

 stated ; but, most probably,it was one of scarcity to the parent animals. The 

 following list exhibits the proportion of the sexes in the annual produce of 

 generally six cows, of the Ayrshire breed (four being the same individuals 

 throughout, the remainder their produce), kept in a park in this neighbour- 

 hood. It commences with the year in which the present superintendent 

 took charge of the stock; and there is no question but that, if the stock-books 

 of other persons who have the care of cattle were to be duly looked over for 

 a series of years, many similar and equally interesting facts would be brought 

 to light : — 



In 1826, from 6 cows, were born 6 male calves, females. 



Thus it appears that, for the first four years, but one female calf was 

 produced out of twenty-three births ; that in the succeeding year the pro- 

 portions were equal ; that in the next four years, out of twenty-two births, 

 there was not a single male; and that in the following year, again, the sexes 

 were in like proportions. The present season, alone, has formed an excep- 

 tion to this remarkable regularity, which I have in vain endeavoured to solve 

 by making every enquiry concerning the male parents. There is some 

 reason, also, to suspect that the same phenomenon will be found to obtain 



