PROTOPLASMIC AND AMCEBOID MOVEMENTS. 7 



more highly organised beings, vegetable as well as ani- 

 mal. All living beings are fundamentally composed of 

 just such lumps of protoplasm as we see in the Amoeba?. 

 Most of these lumps of protoplasm have, however, 

 essentially changed their appearance, and, at the same 

 time, their qualities, so that it is only from the evolu- 

 tion of the parts that we know them to have originated 

 from such lumps. Moreover, even in developed organ- 

 isms separate parts always occur which are in all re- 

 spects similar to such lumps of protoplasm as the 

 Amoeba', and which move like the latter. It is a well- 

 known fact, that when a drop of blood is placed under 



FIG. 2. WHITE BLOOD-CORPUSCLES FROM A GUINEA-PIG. 



a, b, c. Various forms assumed by ouc and the same corpuscle. 



the microscope, a very large number of small red bodies, 

 to which the red colour of the blood is due, are seen 

 within it. And scattered about among these red blood- 

 corpuscles are seen colourless or white blood-corpuscles, 

 round or jagged in form, and containing granular pro- 

 toplasm with a kernel or nucleus. If the blood has 

 been placed on a warmed glass, and if it is observed 

 at a temperature of from 35 to 40 degrees C., these 

 blood-corpuscles exhibit active movements entirely 

 similar to those of the Amoeba', and which have, there- 

 fore, been called Amoeboid movements. The corpuscles 

 send out processes and again retract them ; they creep 

 about on the glass ; and, in short, they behave exactly 



