358 Remarks upon the Theory of Hybridity. 



tlemen present. To place it, therefore, beyond all suspicion, 

 I sent, a little after Christmas, a pair of hybrids, bred as 

 above, to a cottage, in the neighbourhood of which no geese 

 were kept. The male, soon after the female began to lay, 

 was, unfortunately, destroyed. He was, however, in a few 

 days replaced by another, bred in the same manner. To this 

 fact, of the goose having been without a mate for nearly a 

 week, may be attributed that of many of the eggs having been 

 unproductive. Three fine goslings were, however, hatched, 

 and are now alive and doing well, precisely (as far as being 

 intermediate in external character between the Chinese and 

 common goose) similar to their parents, and may be seen any 

 day swimming in the pool with them. 



Not the slightest repugnance is exhibited between the male 

 Chinese and female common goose : they become attached 

 (if I may use the expression) at sight, even if the male has one, 

 or even two, females of his own species at the time with him. 



All my experiments have been made between the female 

 common and male Chinese. Whether the converse will be 

 equally successful, I hope, in the course of next year, to be 

 able to prove, and also to try many other experiments of a 

 similar nature. 



The deduction to be drawn from what I have stated, ac- 

 cording to John Hunter's theory, is self-evident; namely, 

 that the above-mentioned birds are one and the same species. 

 They differ, it is true, materially in form and external cha- 

 racter : but why should we suppose that local circumstances 

 should have a less effect upon animals than upon man himself? 

 The differences between the two supposed species of geese are 

 not greater than those existing between the races of man, or, 

 rather, between those varieties * of the human species found in 

 the two countries from which the two species of geese come. 

 This appears to be in favour of Hunter's theory ; and that the 

 two species are one, altered by climate. 



The number of the vertebrae has not, that I am aware ofj 

 been found to differ in any of the races of man. Whether this 

 is the case, or not, in the two species, or supposed species, of 

 geese, I cannot at present say ; but in three varieties (or species) 

 of the genus Sus they differ most materially (see the Zoological 

 Society's Proceedings for 1837); and this difference is not 

 only in the caudal, but in the lumbar and sacral ones : yet these 

 species breed together, and their offspring are prolific. We 

 must therefore either reject this character, as one determining 

 species ; or the theory of John Hunter : unless, indeed, do- 



* Circassian and Mongolian. 



