170 Tests with Precipitins 



in due course for other families of Primates. The tests I have made 

 with anti-monkey serum arc given in the short table which follows. 

 Before coming to these, I shall refer to a paper by Friedenthal 

 (10, VII. 1902, p. 831). Pursuing my line of investigation, he sought 

 to obtain an antiserum for Cynocephalus hamadryas, the blood of 

 which animal he injected subcutaneously into rabbits in the huge 

 doses of 26 — 51 c.c, which appears to have killed most of his rabbits 

 outright, as might naturally be expected. It is almost impossible to 

 attach any value to his results, because of the faulty manner in which 

 he proceeded to immunify his animals, and especially because of the 

 date at which he bled them after their last injection. In a protocol, 

 which he gives, he states that he obtained an antiserum from a rabbit 

 as follows : A rabbit received monkey serum subcutaneously in doses 

 of 2, 2, 3, 5, 5, 5 c.c, the day intervals between inoculations being 

 3, 2, 5, 5, 4. Bled 3 days after the last injection, the rabbit's serum 

 contained no precipitin for its homologous blood. Having waited 

 seven days, he injected 25 c.c. (!) subcutaneously, and 48 hours (!) 

 later, found precipitin (?) in the rabbit's serum, the serum being then 

 used for tests. He made the tests by adding 0'2 c.c. of the serum 

 to be tested to 5 c.c. of the " antiserum \" 



Although Friedenthal's method was evidently bad, the results he 

 claims to have obtained are not opposed to mine. His antiserum 

 acted on its homologous blood, and also upon that of three other 

 Cercopithecidae {Cynocephalus " dschedala," Colobus guereza, Macacus 

 cynomolgus) to an equal degree. His antiserum, when first used, 

 was certainly very weak (as might be expected from the very 

 early date at which he bled his rabbit after its last injection), 

 for he states that it fiiiled to produce any effect upon human or 

 anthropomoq^hic ape blood even after 24 hours. He adds, later (p. 833), 

 that the rabbits which survived his (mal-) treatment, gave an anti- 

 serum which did also produce reactions, though weaker ones, with 

 both human and chimpanzee blood. In this he confirms my results 

 with the anti-primate sera described on the preceding pages, and also 

 agrees with Avhat follows. It is unfortunate that Friedenthal used 

 such methods, for, as stated, they tend very much to vitiate his results. 



^ See further under " Sources of Error," p. 74. 



