70 



ANATOMY 



A series of determinations on the increase in the number of 

 leucocytes with age, table 32, has been made by Jolly ('19). 



TABLE 32 



Changes in the number of leucocytes with age 

 According to Jolly ('19) the number of leucocytes tends to increase with age 



In the rat before birth the numbers of cells have been deter- 

 mined by Addison and Richter (MS '23). The leucocytes and 

 erythrocytes increase from the 18 day to the 21 day stage 

 while the erythroblasts decrease table 33. 



TABLE 33 



Cells in 1 mm. 3 of prenatal blood (Addison and Richter, MS. '23). The number of 



cases are in parentheses 



TABLE 34 



Red cells and platelets of normal albino rats (condensed from Cramer, Drew and 



and Mottram, '22) 



For the number of blood platelets in normal albino rats data 

 are presented in table 34. 



