Apeil 6, 1906.] 



SCIENCE. 



551 



who, as above stated, recorded large scurs as 

 horns. If the dam was really a hybrid, as I 

 suspect, and the two horned calves in the third 

 group had large scurs instead of horns, the 

 results would agree exactly with the admissible 

 theory that he was a pure poll. On the other 

 hand, no record was made of a number of his 

 get from common cows, so that, on the theory 

 that he was a hybrid, the missing horned 

 calves in group 3 may be the progeny of these 

 unrecorded common cows. 



From the above it will be seen that the only 

 results not agreeing closely with theory are 

 doubtful, while in every case where no doubt 

 exists the results are in very satisfactory 

 agreement with theory. These facts render 

 it highly probable that the polled character is 

 a dominant Mendelian unit character. 



Dehorning a Breed of Cattle. — Assuming 

 the above conclusion to be true, the dehorning 

 of a breed of cattle is fairly simple. A single 

 hybrid animal would suffice for this purpose, 

 though this would require some inbreeding. 

 It would be better perhaps for several breeders 

 to cooperate, so as to avoid the necessity of 

 inbreeding. An occasional polled animal oc- 

 curs in all breeds of cattle, and these can be 

 used in such a manner as to produce a new 

 polled breed. In some instances polled ani- 

 mals of other breeds have furnished the start- 

 ing point, it being possible to transfer the 

 single character desired from one breed to 

 another. 



Suppose several breeders secure polled bulls 

 (either pure polls or hybrids) to head their 

 herds. These are bred to large numbers of 

 horned cows. The get of the pure polls will 

 all be polled hybrids, and half the get of the 

 hybrids, in this case, will be polled hybrids. 

 Now, by breeding these polled hybrids together 

 we get one fourth pure polls, one half hybrid 

 polls and one fourth horned. The pure polls 

 thus obtained may become the basis of the 

 future polled herds. The pure polls can be 

 distinguished from the hybrids as follows: In 

 the first place some (may be all) the hybrids 

 will have scurs. In the second place, we may 

 distinguish them by their progeny. Breed 

 the animal to several horned animals; if the 

 progeny are all polled, the polled parent is a 



pure poll; if half the progeny are horned, the 

 polled parent is a hybrid. 



In the case of males, if we breed to twelve 

 horned cows and secure twelve polled calves, 

 the chances that the male is pure and not a 

 hybrid are 4,096 to 1. (Twelfth power of 

 2^4,096.) If any of the twelve progeny 

 develop perfect horns the chances are great 

 that the bull is a hybrid. 



It is more difficult to determine whether a 

 polled cow is pure or hybrid. If she have 

 scurs, even very small ones, she is hybrid. If 

 not, so far as we now know, she may be either 

 pure or hybrid. If she regularly produces 

 polled calves from horned sires she is pure. 

 But, when breeding for polled animals, it is 

 expensive to test a polled cow in this way. 

 The better plan is to be sure as to the males 

 in all cases and treat all females as pure polls 

 unless they have scurs or horns. In time the 

 horns will disappear from the breed. It is 

 highly important to remember that when a 

 horned calf occurs in a polled breed, either it 

 is a hybrid with horns, a thing not yet cer- 

 tainly known, or both of its parents are hy-, 

 brids. There are undoubtedly a few such 

 hybrids in all polled breeds, and when two 

 such hybrids mate, one fourth of the progeny 

 is horned. The number of such hybrids in a 

 breed may be rapidly reduced by discarding 

 both sire and dam of all horned animals that 

 occur. The same thing will be accomplished 

 less rapidly by discarding only the sires. The 

 occurrence of scurs, but not perfect horns, 

 in an established polled breed indicates that 

 one parent only is hybrid. 



W. J. Spillman. 



U. S. Department of Agbicclture. 



PRELIMINARY NOTES ON THE ARCHEOLOGY OF THE 

 YAKIMA VALLEY, WASHINGTON.' 



Archeological explorations' were made in 

 the Yakima Valley, Washington, for the 

 American Museum of Natural History in the 



' Published by permission of the trustees of the 

 American Museum of Natural History. 



' The first report of these explorations appeared 

 in The American Museum Journal, pp. 12-14, 

 Vol. IV., No. 1, January, 1904. It was slightly 

 revised and appeared in Science, N. S., pp. 579- 



