196 INVERTEBRATE ZOOLOGY 
and in the course of time will die. Conjugation also occurs, as 
in other Protozoa. The processes of division and conjugation 
apparently do not take place frequently, as they have not been 
often observed. 
About a dozen species of the genus Amoeba are known. 
The commonest are probably A. proteus, a large, often active 
form with long pseudopodia, .A. verrucosa, a large, sluggish form 
with very short pseudopodia, A. limaz, a small form which flows 
along without definite pseudopodia, and A. radiosa, a small 
star-shaped form with slender, radiating pseudopodia. 
