50 SPECIFICITY OF THE BLOOD OF VERTEBRATES 



The researches in recent years by Arronet, Daland, Koppe, Puffer, 

 and others (Vierordt's Daten u. Tabellen, 1906, 197), with human blood 

 show that the mean percentage in men is approximately between 45 and 

 50 per cent and in women about 3 to 8 per cent less. 



TABLE 19. The percentages of corpuscles in the blood of various 

 classes of animals and genera. 



Besides Abderhalden's analyses of the bloods of the cat, dog, bullock, 

 sheep, goat, horse, pig, and rabbit, there are a few scattered records by 

 Sacharjin, Fudakowski, Hohlbeck, Otto, Bliebtreu, and others (Sacharjin, 

 Hoppe-Seyler's Physiologische Chemie, 1887, 447; Bunge, Zeit. f. Biologic, 

 1876, xii, 191; Fudakowski, Centralblatt f. med. Wissensch., 1866, iv, 

 705; Hohlbeck, Hoppe-Seyler's Physiologische Chemie, 1877, 447; Otto, 

 Archiv f. ges. Physiologic, 1885, xxxv, 467; Bliebtreu, ibid., 1892, LI, 151; 

 Arronet, Inaug. Dissert., Dorpat, 1887), but for comparison the quite recent 

 work of Abderhalden will best serve our purposes. The highest percentage 

 is for the pig, 43.59 per cent, and then in the following order: cat 43.4 per 

 cent, dog 42.01 per cent, horse 39.77 per cent, rabbit 37.21 per cent, goat 

 34.72 per cent, bullock 33.55 per cent, and sheep 31.28 per cent. Grouping 

 the individuals in classes, the omnivora (man and pig) stand first, then 

 the carnivora (dog and cat), then the horse and rabbit as representatives 

 of their classes, and finally the ruminants. 



THE BLOOD PLATELETS IN RELATION TO GENERA. 



Blood platelets are found in abundance (from 200,000 to 600,000 per 

 cubic millimeter) in mammalian blood, but they are absent from the bloods 

 of birds, amphibia, and fish, in which there exist what are probably homol- 

 ogous structures in the form of small nucleated spindle-shaped cells. 



THE FORM OF THE ERYTHROCYTES IN RELATION TO GENERA. 



All the vertebrates are divisible primarily into two classes in accord- 

 ance with the presence of non-nucleated or nucleated red corpuscles, and 

 further divisions and subdivisions may be made through distinctions in 



