18 



THE BLOOD 



Red Corpuscles. The red blood-corpuscles (erythrocytes) constitute 

 about fifty per cent of the entire mass of blood. (Flint, 1863.) Their 



Fig. 14. Blood-corpuscles from certain of the inferior animals, compared with corpuscles from the 



human subject, X 700. 



The measurements in these figures are taken from Gulliver (1841), and for the elliptical cells the 

 long diameters are given. In the original article by Gulliver about five hundred measurements are given. 

 I published one hundred of these in the Physiology of Man, 1866, Vol. I, p. 113. For the conven- 

 ience of readers, the English measurements have been reduced to microns. 



A. Man, ^g inch = 8.0 M. 



B. Whale, 3^3 inch = 8.2 m. 



C. Elephant, s- 1 ^ inch = 9.2 M. 



D. Mouse, ?5 Vc inch = 6.0 M. 

 . Horse, jeW inch = 5.5 M. 



F. Musk-deer, 15351; inch = 2.0 M. 



(7. Camel, 3^3 inch = 8.1 M. 

 //. Humming-bird, 5^5 inch = 9.6 M. 



/. Pheasant, 5155 inch = 12.0 M. 



yr. Pigeon, 53 1 u inch = n.o M. 



Z. Ostrich, tgsg inch = 15.4 M. 



A/. Lizard, ^35 inch 

 N. Snake, isV? inch 

 O. Crocodile, i^ai inch 

 P. Toad, r &3 inch 

 ^). Triton, 5 i? inch 

 A J . Proteus, ? uo inch 

 S. Perch, 5^1 inch 

 T. Pike, snVo inch 

 f/. Electric eel, 

 V. Shark, j&a 



= 16.3 ft. 



= 2O.O M. 

 = 2O.6 M. 

 = 24.3 ** 

 =31.2 M. 



= 63.5 ' x - 

 = 10-3 fx. 

 = 12.7 M-. 



inch = 14.8 M. 



= 22.2 M.. 



form is peculiar and distinctive. Many are circular, and thinner at the 

 central portion than at the periphery, where the stroma is more dense 

 and consistent. 



