70 THE BLOOD. 



two principal forms, the red and the white corpuscles. 

 When coagulation has taken place quickly, both kinds of 



Fig. 24-* 

 Mammals. Birds. Eeptiles. Amphibia. Fish. 



* The above illustration is somewhat altered from a drawing, by Mr. 

 Gulliver, in the Proced. Zool. Society, and exhibits the typical characters 

 of the red-blood cells in the main divisions of the Vertebrata. The 

 fractions are those of an inch, and represent the average diameter. In 



