26 



HANDBOOK OF PROTOZOOLOGY 



Rhizopodia. These are branching (reticulopodia) or anasto- 

 mosing (myxopodia) temporary cytoplasmic projections. They 

 are commonly found in Foraminifera (Fig, 76) and Testacea 

 (Fig. 94). ^ 



Axopodia. These are more or less straight, filamentous, and 

 usually radiating, semi-permanent pseudopodia widely present 

 in Heliozoa (Fig. 98) and Radiolaria (Fig. 104). They possess 

 an axial filament which is surrounded by a thin layer of cyto- 

 plasm. The latter undergoes a constant movement. The axial 

 filament may originate in the "central granule," a special basal 

 body, or in the general cytoplasm. 



Fig. 7 Vahlkampfia Umax, showing different pseudopodia. (After Verworn). 

 a,b, contracted forms; c, individual siiowing typical appearance; d-f, "radiosa" 

 forms, after addition of potassium hydrate solution to the water. 



While the pseudopodia formed in an individual are usually of 

 characteristic form and appearance, they may show an entirely 

 different appearance under certain circumstances. According to 

 the often-quoted experiment of Verworn, "limax" amoebae 

 change into "radiosa" amoebae upon addition of potassium 

 hydrate to the water (Fig. 7). In some cases during and after 



