182 Transplantation and Growth of Mammalian Ova. 



all closely resembled their Dutch father, but three of them were 

 apparently thorough-bred Belgian Hares ; it certainly seems that in 

 the case of these animals the Belgian Hare strain is much the 

 stronger of the two; at the same time the father's influence is seen 

 in the very general introduction of white and in the fawn and dun 

 colours of certain of the young. 



With regard to the foster-children, one of them unfortunately died 

 at an early age, but the second one lived and is now more typically 

 Dutch than it was when very young. It is coloured like its mother, 

 fawn and white, and has no trace of the bluish dun shade noticeable 

 here and there in its father's coat. Its head, feet, and legs, are 

 remarkably like its mother's, the saddle on the back is fairly well 

 defined, especially on one side, and the main faults are white tips 

 to the ears and patches of white across the fawn colour of the back 

 and sides. 



In reviewing the whole question one may claim : — 



(1) That in two litters got by the Dutch buck out of Belgian 

 Hare does, there were ten young ones, not one of which so 

 nearly approaches the Dutch type as does the single Dutch 

 young one borne by the Belgian Hare foster-mother. 

 ! (2) That the bad marking of the young got by the Dutch buck 

 out of a pure-bred Dutch doe is shown to be the fault of the 

 father, and that, consequently, it is not surprising his other 

 offspring, the foster-child, should also be badly marked. 



(3) That the probability of the Dutch buck begetting character- 



istic Dutch young when crossed with a doe of another 

 species, is reduced to a minimum ; while, on the other hand, 

 the probability is increased that a young one, with such 

 strongly marked Dutch characteristics as the foster-child is 

 possessed of, is derived from the ovum of a Dutch mother. 



(4) That the chance of producing a cross-bred young one out of 



the Belgian Hare foster-mother by the help of Dutch 

 spermatozoa, which was twenty -four or more hours old 

 when introduced into her fallopian tube, is remote; and is 

 rendered still more improbable when it is remembered that 

 fresh Belgian Hare spermatozoa in ample quantity would 

 also be present. 



(5) That the similarity of the result now obtained with that 



obtained in 1890, is striking evidence in favour of my con- 

 tention that these experiments present strong evidence 

 towards the proof, (1) that it is possible to make use of the 

 uterus of one variety of rabbit as a medium for the growth 

 and complete foetal development of fertilised ova of another 

 variety of rabbit ; and (2) that the uterine foster-mother 



