Mr. F. Galton's Experiments in Pangenesis. 373 



bred faster than a free gemmule, an influx of new immigrants would 

 gradually supplant the indigenous gemmules ; under which supposi- 

 tion, a rabbit which, at the age of six months, produced young 

 which reverted to ancestral peculiarities, would, when five years old, 

 breed truly to his individual peculiarities ; but of this there is no 

 evidence whatever. 



Under Mr. Darwin's theory, the gemmules in each individual 

 must therefore be looked uj)on as entozoa of his blood, and, so far 

 as the problems of heredity are concerned, the body need be looked 

 upon as little more than a case which encloses them, built up through 

 the development of some of their number. Its influence upon them 

 can be only such as would account for the very minute effects of use 

 or disuse of parts, and of acquired mental habits being transmitted 

 hereditarily. 



It occurred to me, when considering these theories, that the truth 

 of Pangenesis admitted of a direct and certain test. I knew that the 

 operation of transfusion of blood had been frequently practised with 

 success on men as well as animals, and that it was not a cruel opera- 

 tion — that not only had it lieen used in midwifery practice, but that 

 large quantities of saline water had been injected into the veins of 

 patients sufi*ering under cholera. I therefore determined to inject 

 alien blood into the circulation of pure varieties of animals (of 

 course, under the influence of anaesthetics), and to breed from them, 

 and to note whether their offspring did or did not show signs of 

 mongrelism. If Pangenesis were true, according to the interpreta- 

 tion which I have put upon it, the results would be startling in their 

 novelty, and of no small practical use ; for it would become pos- 

 sible to modify varieties of animals, by introducing slight dashes of 

 new blood, in ways important to breeders. Thus, sup|)0sing a small 

 infusion of bull-dog blood was wanted in a breed of greyhounds, this, 

 or any more eoiiiplicated admixture, might be effected (possibly by 

 operating through the umbilical cord of a newly born animal) in a 

 single generation. 



I have now made experiments of transfusion and cross-circula- 

 tion on a large scale in rabbits, and have arrived at definite results, 

 negativing, in my opinion, beyond all doubt, the truth of the doctrine 

 of Pangenesis. 



The course of my experiments was as follows : — Towards the end 

 of 18G9, I wrote to Ur. Sclater, the Secretary of the Zoological 

 Society, explaining what I proposed to do, and asking if I might 

 be allowed to keep my rabbits in some uimsed part of the Gardens, 

 i)eeause 1 had no acconunodation for them in my own house, and I 

 was also anxious to obtain the skilled advice of Mr. iJartlett, the 

 ISiiperintendent of the Gardens, as to their breed and tlie value of my 

 results. I further asked to be permitted to avail myself of the ser- 

 vices of their then Prosector, Dr. Murie, to make the operations, 

 whose skill and long experience in miiuite dissection is well known. 

 I have wariidy to thank Dr. Sclater for the large assistance he has 

 rendered to me, iii grarutiiig all 1 asked, to the full, and more than to the 

 full ; and I have especially to express my obligations to the laborious 



