CHAPTER XIV. 



BLOOD CORPUSCLES. 



The relative number of red disks to the colorless cells is said to 

 be, on the average, 350 to 1. This is true of the blood drawn 

 from the fine vessels by puncture. While in the vessels the blood 

 must contain a greater proportion of the colorless cells, for by 

 the ordinary method of obtaining blood for examination, they do 

 not flow out of the punctured capillaries as readily as the red 

 disks ; and, moreover, many of them become disintegrated very 

 shortly after they are removed from the circulation. Although 

 the number of red disks normally alters but little, the relative 



Human Blood after death of the elements. The red corpuscles are seen in different 

 positions showing their shape, some also in rolls. Only one white cell (w) is seen, mis- 

 shapen and entangled in fibrin threads. 



number of red to white varies very much on account of the 

 constant changes occurring in the number of the white cells, 

 which has been found to differ according to the observer, the 

 situation, and other circumstances, as shown in the follow- 

 ing table, which gives the number of red corpuscles to one 

 colorless cell. 



Observer's estimate of normal proportion : 



Red. White. 



Welcker, 3351 



Moleschott, 3571 



In various parts of the circulation : 



Splenic vein, 60 1 



Splenic artery, 22601 



227 



