42 SPECIFICITY OF THE BLOOD OF VERTEBRATES 



in the horse, pig, and rabbit, but we do not find the marked differences 

 in the ratios that were described in the case of Na, K, and P 2 O 5 , although 

 the group distinctions appear in accord with the Na, K, and P 2 5 records. 

 In the goat, horse, pig, and rabbit the ratios are relatively low; in the car- 

 nivora higher; and in the ruminants, excepting the goat, the highest. The 

 quantitative differences in the bullock, sheep, and goat in the blood and 

 corpuscles are striking and indicate generic distinctions. 



TABLE 15. The percentages and ratios of cholesterin in the bloods, 

 sera, and corpuscles of different animals. 



THE PROTEINS OF THE SERUM IN RELATION TO GENERA. 



The percentage of proteins in the sera of different species and of individ- 

 uals of the same species is variable, and even in the same individual it is 

 not constant under either normal or abnormal conditions. Notwithstand- 

 ing these differences the important fact has been demonstrated by both 

 Salvioli (Archiv f. Anat. u. Physiologic, 1881, 269) and Hoffmann (Archiv 

 f. path. Anat. u. Physiolog., 1882, LXXXIX, 27) that, while the total per- 

 centage of proteins is variable, the "protein quotient" (percentage of 

 serum globulins divided by the percentage of serum albumins) in any given 

 species or individual remains quite constant. The former has also shown 

 that in dogs this quotient for serum, chyle, and lymph is practically the 

 same, although the percentages of albumins and globulins may vary 

 considerably. The ratio between serum albumins and serum globulins may 

 therefore be of zoological significance. 



The total percentage of proteins in the sera of warm-blooded animals 

 is, on the whole, higher than in the cold-blooded animals, in the former 

 the mean being a little less than 7 per cent and in the latter a little over 

 4 per cent (table 16). In mammals the range is between 5.357 per cent 

 in the rabbit and 8.424 per cent in the horse. Such differences as exist in 

 the percentages of protein do not indicate any of the group differentiations 

 that were pointed out in the case of Na, K, P 2 5 , and cholesterin. On the 

 other hand, the protein quotients differ so decidedly as to indicate generic 

 peculiarities. In other words, the proportions of globulins and albumins 

 vary markedly in different genera. 



