THE BLOOD PLATES 



133 



FIG. 116 (a) Red blood corpuscle for comparison; (b) Small lymphocyte; (c) 

 Large lymphocyte (myelocyte); (d) Fine and (e) coarse eosinophiles; (/) Basophile. 

 (F. C. Busch.) 



Ameboid Movement and Phagocytic Action of Leucocytes. The remark- 

 able property of the colorless corpuscles of spontaneously changing their 

 shape was first demonstrated by 

 Wharton Jones in the blood of the skate. 

 If a drop of blood be examined with 

 a high power of the microscope, under 

 conditions by which loss of moisture is 

 prevented, and at the same time the 

 temperature is maintained at about that 

 of the body, 37 C., the colorless corpus- 

 cles will be observed slowly to alter 

 their shapes, and to send out processes 

 at various parts of their circumference. 

 The ameboid movement which can be 



demonstrated in human colorless blood FlG Il8 ._ Blood Plates> showing 

 Corpuscles can be most conveniently chromatic centers regarded by some as 

 studied in the newt's blood. Processes 

 are sent out from the corpuscle. These 

 may be withdrawn, but more often the protoplasm of the whole corpuscle 

 flows gradually forward to the position occupied by the process, thus the 

 corpuscle changes its position. The change of position of the corpuscle 

 can also take place by a flowing movement of the whole mass, and in 

 this case the locomotion is comparatively rapid. The activity both in 

 the processes of change of shape and also of change in position is much 

 more marked in some corpuscles than in others. Klein states that in the 



