and subsequent p oss ible Fertilisation of their Ova. 53 



Certain other mammals, however, differ from the rabbit in the 

 matter of ovulation. Sobotta (No. 34) has shown that mice ovulate 

 prior to the act of copulation, and Tafani's (No. 36) researches point 

 to the same conclusion for rats, though whether the animals used for 

 these investigations were virgins or not is not stated. 



Spallanzani (No. 35), Pierre Rossi (No. 27), and Sir Everett 

 Millais's experiment on bitches, to which I refer below, show that 

 the act of copulation is not necessary to bring about ovulation in 

 these animals ; certain other writers have shown that the same is 

 true for the mare, and the researches of various medical experts 

 demonstrate a similar possibility for the human female. 



According to Hausmann (No. 12), sheep do not ovulate unless 

 copulation takes place, but it is not improbable that many, if not 

 most, of the lower mammals will be found to ovulate independently 

 of the act of coition. In order to prove this fact, as my researches 

 on the rabbit will show, other evidence must be sought for than the 

 fallacious evidence of the appearance of the so-called corpora lutea 

 in the ovaries (Pou'chet, No. 26). 



The possibility of artificially inseminating mammals in which 

 ovulation takes place independently of coition, has seemed to me well 

 worthy of notice, and the following short account has been written 

 for the purpose of drawing attention to a subject which has appa- 

 rently been much neglected, and with the hope that it may induce 

 observers to record anew experiments of which I have been unable 

 to find records and facts bearing upon it which are not alread}^ 

 known. The importance of the subject is not, I think, fairly recog- 

 nised, but I believe that a fuller knowledge of what is known about 

 it will show that it is a matter of great interest both from a scientific 

 and a practical point of view. 



It has been ascertained that if spermatozoa be placed artificially 

 in the vagina of certain female mammals at the right season, they 

 may conceive ; it has been ascertained also that if spermatozoa be 

 placed artificially within the uterus of certain individual mammals 

 which have failed for particular reasons to breed by natural means, 

 they may become pregnant in consequence ; and there is little 

 doubt that an extended study of the subject will throw light on the 

 physiolog.cal relations of coition and insemination, ovnlation and 

 fertilisation, and oh certain of the causes which induce sterility in 

 mammals, which will be of great interest to physiologists and of 

 great value to practical breeders. 



There is another, a wider but more problematical direction in 

 which a fuller knowledge of the possibilities of artificial insemination 

 may induce experiment ; I mean the crossing of varieties or of species 

 that will not naturally breed together. 



I am not aware of any proof that any mammalian spermatozoon is 



e 2 



