244 



Dr. J. C. Ewart. 



It may for all we know be as old as the belief in " mental impressions/' 

 which has had its adherents since at least the time of the patriarchs. 

 During the eighteenth century the " infection " doctrine was frequently 

 discussed by physiologists, and since Lord Morton, in 1820, addressed 

 a letter to the Royal Society on the subject, believers in " infection " 

 have been increasing all over the world, with the result that one seldom 

 now hears of breeders or fanciers who are not influenced by the doc- 

 trine, while physicians and others interested in the problems of here- 

 dity either as a rule take telegony for granted or see nothing improbable 

 in the " infection " hypothesis. 



It must, however, be admitted that, notwithstanding the criticisms of 

 Weismann and others, very different views are entertained by the 

 believers in telegony, not only as to the cause, but as to the results, of 

 " infection." By some telegony is confounded with simple reversion or 

 atavism, while the better informed generally assume that " infection " 

 invariably results in the subsequent offspring repeating more or less 

 accurately the characters of the first or of a previous sire. In a 

 breeders' journal of some standing there appeared recently under the 

 heading " Colour of Animals " the following sentence : — " Greys show 

 in breeding a great tenacity of assertion, as they are few in comparison 

 to other colours in the Stud Book, but they reappear and no doubt go 

 back to the Arab, and prove telegony to be a fact."* This shows 

 simple reversion is sometimes mistaken for telegony. In support of 

 the view that " infection " is commonly supposed to lead to " throwing 

 back " to a previous sire many instances could be given, but the follow- 

 ing from an article on telegony by De Varigny will suffice. De Varigny 

 states that an ordinary cat which had kittens to a tailless Manx cat 

 subsequently produced several tailless kittens to a normal cat of her 

 own breed, f 



An extended series of experiments with various kinds of animals has 

 led me to the conclusion that if there is such a thing as telegony, it is 

 more likely to result in the subsequent offspring "throwing back " to an 

 ancestor of the " infected" dam than to a previous mate. This view of 

 telegony (which has not been insisted on hitherto) will be made at once 

 evident by an example. A sable collie crossed with a Dalmatian pro- 

 duced three pups which in their coloration are extremely like young- 

 foxhounds ; instead of numerous small spots each has a few large 

 blotches. According to the common view of telegony this collie, if 

 infected, should next produce with a dog of her own breed one or more 

 Dalmatian-like pups. If, however, the offspring of a collie and a Dal- 

 matian are like foxhounds, the subsequent offspring to a collie of the 

 same colour and strain could hardly be expected to present Dalmatian 

 characters, i.e., show numerous small spots. But if " infection " as a 



* ' Live Stock Journal/ May 12, 1899, p. 588. 

 f ' Journal des Debats,' September 9, 1897. 



