LYMPH. 49 



brates, vary considerably. In all the class of the mammalia 

 they are circular biconcave disks, with the exception of the 

 camel tribe, in which they are oval. They vary in diam- 

 eter from .002 mm.* (musk deer) to .011 mm.f (elephant). 

 In the dog they are nearly the same size as those of man. 

 In no mammals do the fully developed red corpuscles pos- 

 sess a nucleus. In all other vertebrate classes the red cor- 

 puscles possess a central nucleus, and are oval slightly 

 biconvex disks, except in a few fishes in which they are cir- 

 cular. They are largest of all in the amphibia. Those of 

 the frog are 0.02 mm. (y^Vo" incn ) lon g and 'W? mm 4 

 broad . 



Histology of Lymph. Pure lymph is a colorless watery- 

 looking liquid; examined with a microscope it is seen to 

 contain numerous pale corpuscles exactly like those of the 

 blood, and no doubt largely consisting of pale blood cor- 

 puscles which have emigrated. It contains none of the 

 red corpuscles. The lymph flowing from the intestines 

 during digestion is, as already mentioned, not colorless, but 

 white and milky. It is known as chyle, and will be con- 

 sidered with the process of digestion. During fasting the 

 lymph from the intestines is colorless, like that from other 

 parts of the Body/ 



inch. \ j^ inch. i 



