1871.] Mr. F. Galton's Experiments in Pangenesis. 



403 



way, to breed from them in seven instances ; and five of them were utter 

 failures. One case was quite successful ; and that, fortunately, was of the 

 same pair (A (u) and M (u, w)) which, under the u operation, had bred 

 the white-footed young one. This time, the offspring (six in number) 

 were pure silver-greys. The last case was unfortunate. The doe (E (w)) 

 had been once sterile to its partner (N (u, w)\ and she had been put again 

 in the same hutch with him for a short period, but was thought not to 

 have taken him. She was shortly afterwards submitted to the operation or. 

 From this she had nearly recovered when she brought forth an aborted 

 litter and died. I was absent from town at the time ; but Mr. Fraser, who 

 examined them, wrote to say he fully believed that some were pied ; if so, 

 it must have been under the influence of the cross-circulation. But I have 

 little faith in the appearance of the skin of naked, immature rabbits ; for I 

 have noticed that difference of transparency, and the colour of underlying 

 tissues, give fallacious indications. 



My results thus far came to this, viz. that by injecting defibrinized blood 

 I had produced no other effect than temporary sterility. If the sterility 

 were due to this cause alone, my results admitted of being interpreted in a 

 sense favourable to Pangenesis, because I had deprived the rabbits of a 

 large part of that very component of the blood on which the restoration of 

 tissues depends, and therefore of that part in which, according to Pan- 

 genesis, the reproductive elements might be expected to reside. I had 

 injected alien corpuscles but not alien gemmules. The possible success of 

 the white foot, in my first litters, was not contradicted by the absence of 

 any thing of the sort in my second set, because the additional blood I had 

 thrown in was completely defibrinized. It was essential to the solution of 

 the problem, that blood in its natural state should be injected ; and I 

 thought the most convenient way of doing so was by establishing cross- 

 circulation between the carotids. If the results were affirmative to the 

 truth of Pangenesis, then my first experiments would not be thrown away ; 

 for (supposing them to be confirmed by larger experience) they would 

 prove that the reproductive elements lay in the fibrine. But if cross- 

 circulation gave a negative reply, it would be clear that the white foot was 

 an accident of no importance to the theory of Pangenesis, and that the 

 sterility need not be ascribed to the loss of hereditary gemmules, but to 

 abnormal health, due to defibrinization and perhaps to other causes also. 



My operations of cross-circulation (which I call x) put me in possession 

 of three excellent silver-grey bucks, four excellent silver-grey does, and 

 one doe whose operation was not successful enough for me to care to count 

 it. One of my x does (B) had already undergone the operation u, and I 

 had another of my old lot (C (w)), which I left untouched. There were 

 also three common rabbits, bucks, which were blood-mates to silver-greys, 

 and four common rabbits, does, also blood-mates of silver-greys. From 

 this large stock I have bred eighty-eight rabbits in thirteen litters, and 

 in no single case has there been any evidence of alteration of breed. There 



