6 ANIMAL LIFE 
drawing in. The single protoplasmic cell which makes up 
the body of the Ameba has no fixed outline; it is a cell 
without a wall. The substance of the cell or body is proto- 
plasm, semiliquid and colorless. The changes in form of 
the body are the moving of the Ameba. By close watching 
it may be seen that the Ameba changes its position on the 
glass slip. Although provided with no legs or wings or 
Fie. 2.—An Ameba, showing different shapes assumed by it when crawling. 
—After VERWORN. 
Scales or hooks—that is, with no special organs of locomo- 
tion—the Ameba moves. There are no muscles in this tiny 
pody; muscles are composed of many contractile cells 
massed together, and the Ameba is but one cell. But it is 
a contractile cell; it can do what the muscles of the com- 
plex animals do. 
If one of the finger-like projections of the Ameba, or, 
indeed, if any part of its body comes in contact with some 
other microscopic animal or plant or some small fragment 
of a larger form, the soft body of the Ameba will be seen 
