1904.] on Anthropoid Apes. 635 



logy has been the study of the properties of blood serum. When 

 the blood of one mammal is injected into the body of another, the 

 blood of the latter animal shows remarkable modifications. If a few 

 drops of the blood of a guinea-pig be added to the colourless fluid 

 known as serum, prepared from the blood of another rodent, say a 

 rabbit, no change takes place. If, however, the blood of the 

 rabbit, before the serum has been prepared from it., be treated by the 

 injection into the living animal of guinea-pig's blood, then the rabbit 

 serum, contaminated so to speak with guinea-pig, shows new pro- 

 perties. It has become a delicate test for guiuea-pig blood. If a few 

 drops of such blood be placed in it, the mixture becomes opaque and 

 reddish, as the guinea-pig blood corpuscles now dissolve in it. If 

 clear guinea-pig's serum be added, in a few minutes a cloudy pre- 

 cipitate is thrown down. Such reactions are sometimes strictly 

 specific, and form a most delicate test for the blood of an animal. It 

 has been found, in the case of the anthropoid apes and man, that the 

 test does not discriminate between the bloods of these forms. In the 

 literal sense of the words, there is an extremely close blood relation- 

 ship between man and the anthropoid apes. This blood relationship 

 is shown in that a number of diseases hitherto thought peculiar to 

 man can be shared by the anthropoid apes. At the Pasteur Institute 

 in Paris, and at the School of Troj)ical Medicine in Liverpool, this 

 physiological kinship is being the basis of a number of experiments 

 which may lead to consequences not only of vast scientific interest, 

 but of the greatest practical imjDortance to man. 



Finally, since Darwin and Huxley wrote, a considerable know- 

 ledge of the embryological development of anthropoid apes has been 

 gained, and this knowledge has revealed the expected but important 

 fact, that, until a very late period before birth, the embryos of 

 anthropoid apes are extremely similar to those of man. 



The gap between man and the lower animals is widening rapidly. 

 In recent geological times species of anthropoid apes more man-like 

 than the existing forms, and species or varieties of the human race 

 more ape-like than existing man, have been blotted out. At the 

 present day the lower races of man are disappearing, and there is 

 more than a probability that the range of the anthropoid apes will 

 become more restricted, and that these too are in danger of extinction. 

 So far, the efforts to keep these apes in captivity have been uniformly 

 unsuccessful, both in the troj^ics and in temperate regions. Gorillas 

 have rarely lived more than a few weeks in captivity ; orangs a few 

 months, reaching in the extreme two or three years ; there has been 

 greater success with chimpanzees. However, none of the larger 

 anthropoid apes have bred in captivity, and breeding must be taken 

 as the absolute test of successful conditions. 



[The lecturer then reviewed some of the difficulties that arise in 

 connection with the keeping of apes in captivity, and stated his 

 belief that the problem of successful confinement was capable of 

 being solved.] 



