HYBRID CATTLE 
249 
1868 in the London Zoological Gardens, the sire 
being a zebu and the dam a gayal.^ This hybrid 
cow was crossed five times subsequently with the zebu, 
and each time produced offspring. Later on she was 
crossed with a bull American bison, and in due 
course gave birth to a female zebu and gayal and 
bison hybrid, which was in turn again crossed with a 
bull bison, and produced offspring. Complete fertility 
is thus shown to have taken place in this series of 
crosses, in which the sire was at first a zebu but 
subsequently a bison. In the final cross the calf was 
essentially of the bison type. 
The American bison has been frequently crossed 
in its native country with European cows, and the 
cross, like the resulting hybrids, has proved perfectly 
fertile ; although all attempts to make bison cows breed 
with European bulls have proved unsuccessful. In these 
cross-bred cattle the characters of the male parent are 
dominant, a ten-months-old steer described and figured 
by Dr. W. T. Hornaday^ being essentially a bison 
in appearance and characters. An adult hybrid cow 
depicted in the same volume is also very buffalo-like. 
" The half-breeds," according to a correspondent 
quoted by Dr. Hornaday, " are very prolific. The 
cows drop a calf annually. They are also very 
hardy indeed, as they take the instinct of the buffalo 
[= bison] during the blizzards and storms, and do 
not drift like native cattle. They remain upon the 
open prairie during our severest winters, while the 
thermometer ranges from 30 to 40 below zero, with 
little or no food except what they found on the 
^ See A. D, Bartlett, Proc. Zool. Soc. London, 1884. p. 400. 
^ " The Extermination of the American Bison," Rep. U.S. Nat. Mus., 
Washington, for 1886-87, p. 4 4, 1889. 
