134 POPULAR SCIENCE MONTHLY. 



miscarried. Here — if there is anything in the direct infection theory 

 — the unused germ-cells of the zebra had a better chance than usual 

 of reaching the ova from which future offspring are to arise, yet neither 

 of the two foals which this mare subsequently produced to a thorough- 

 bred horse "in any way suggests a zebra." 



The above is the record of the successful experiments which have 

 been tried at Penycuik, with a view of throwing light on the existence 

 of telegony in the Equidae. Experiments have also been made with 

 other animals, such as rabbits, dogs, pigeons, fowls, and ducks. Space 

 allows us to quote but one. Six white doe rabbits, all of which 

 had borne pure white offspring to white bucks, were crossed with wild 

 brown rabbits. The result was forty-two young rabbits, all of a bluish- 

 black color, which in a very short time turned to a brown. These, at 

 the time of writing, were about half grown, and Professor Ewart. teiis 

 us that it is almost impossible to distinguish them from a full-blooded 

 wild rabbit kept in the same inclosure. The half-breeds, however, 

 were tamer and slightly lighter in color.' The mother does next bred 

 with white bucks again, and in every case bred true. The pure white 

 young showed no trace of throwing back to a previous sire. 



A phenomenon somewhat similar to telegony, and one which seems 

 at present quite unexplained, is that a hen which has been crossed 

 with a cock of another breed often lays eggs whose shell is no longer 

 like that of its own breed, but in color, and frequently in texture, 

 resembles that of the breed with which it has been crossed. When one 

 calls to mind that the shell is deposited by a special shell-gland which 

 is in no way connected with the ovary, but is a part of the quite 

 distinct oviduct, and that the change in the color of the eggshell 

 must be caused by some change brought about in this gland by cross- 

 fertilization, we begin to recognize how mysterious and inexplicable 

 are many of the problems which affect breeding. 



Throughout his account of his experiments Professor Ewart is 

 extremely cautious in claiming to prove anything, but we think he has 

 justified his claim to have shown that telegony by no means always 

 occurs, as many breeders believe. His experiments so far support the 

 view of Continental mule breeders, that telegony, if it takes place, 

 occurs very seldom. But the experiments are not complete, and it is 

 much to be hoped that they may be continued. If it should subse- 

 quently appear that out of fifty pure-bred foals from dams which have 

 been previously mated with the zebra no single instance of telegony be 

 found, the doctrine may surely be neglected by breeders; and if in the 

 experiments which are now being carried out with various other mam- 

 mals and birds telegony does not occur, the doctrine may be relegated 

 to the 'dumping-ground' of old superstitions. The present state of 

 the matter may be summed up in the professor's own words: "The 



