﻿1XXV1 3PK0CEEDINGS OF THE GEOLOGICAL SOCIETY. [May 1 9 10, 



pointing to a very close connexion between ]VIan and the anthropoid 

 apes, which has been afforded during the last decade by a novel 

 method of investigation. The germ of this method is to be found 

 in those famous discoveries by Behring, to which we owe the serum 

 treatment for diphtheria. It was these that led Uhlenhuth to 

 undertake the experiments on blood-relationship to which I will 

 now refer. In his first experiments he made use of ordinary white 

 of egg ; a solution of this was injected into a living rabbit, and 

 after some days the rabbit was bled. The serum of the blood so 

 obtained was then found to give a precipitate when mixed with the 

 white of a hen's egg, but not with that of a duck's egg or, indeed, 

 any other kind of egg. 1 In his next experiments Uhlenhuth 

 substituted the blood of a hen for the white of its egg. The serum 

 of the rabbit's blood was then found to give a precipitate with hen's 

 blood, but with no other kind of blood. The blood of other animals 

 was similarly injected, and found to produce a serum which gave 

 similar results. 



Further experiments showed that the test was not perfectly 

 diagnostic, since the blood of animals closely related to the one 

 whose blood had been injected also gave a precipitate with the 

 resulting serum, though not in so large an amount. Thus the 

 injection of horse's blood produces a serum which gives a weak 

 precipitate with ass's blood, sheep's blood with goat's blood, and 

 so on." 



Thus the method provides not only a means of identifying a 

 particular kind of blood, but of estimating the degree of relationship 

 between the blood of different kinds of animals. It was applied by 

 Uhlenhuth to the Primates. Human blood was injected into a 

 rabbit, and a serum obtained which gave a precipitate not only with 

 human blood, but with that of the man-like apes ; on the other 

 hand, it gave no precipitate with the blood of the lower apes. 



The investigation was then greatly extended by Mr. G. H. Nuttall, 

 who made a vast number of comparative experiments, and introduced 

 more exact quantitative methods. 3 As one result, it was shown 



1 Uhlenhuth, Deutsch. Med. Wochenschr. 1900, No. 6; an excellent 

 summary is given in the same author's ' Ein neuer biologischer Beweis f. d. 

 Blutverwandschaft zwischen Menschen- & Affengeschlecht.' Corresp. Bl. 

 Deutsch. Gresellsch. Anthrop. Miinchen, vol. xxxv (1904) p. 114. 



2 Injections of the juice of flesh had precisely similar effects upon the blood 

 of the rabbit, the serum giving a precipitate with the juice of the same kind of 

 flesh as that which bad been employed for the injections ; in this way a means 

 was discovered for detecting horseflesh in sausages. 



3 'Blood Immunity and Blood Belationship, &c.' Cambridge, 1904. pp. 444. 



