AMGBA COLI. 641 
The body consists of two portions: the inner one, 
which is more or less granular and of a darker color, 
is known as the entoplasma; the outer one, which is 
homogeneous and of a lighter color, as the ectoplasma 
(see Plate II., Fig. 10). This division into two zones 
cannot always be made out, and is more evident in the 
motile than in the resting ameeba. 
The entoplasma constitutes the greater portion of the 
body of the amceba, being usually centrally situated, 
but occasionally slightly eccentric. In the smaller 
forms of amcebe it is finely granular, and may show 
no other structure. In the larger forms it is more 
coarsely granular, and often contains clear, circular, 
and slightly oval spaces known as vacuoles. These 
are extremely variable in number and size. 
The ecloplasma is quite homogeneous, forming a zone 
of variable thickness around the entoplasm. It has 
the appearance of finely ground glass of a distinctly 
pale green tint. 
In most amoebe a nucleus can be seen. Its detection 
is not always possible in fresh or motile amcebe, but 
under certain conditions in the motionless or dead 
amcebee the nucleus becomes evident, and it may be 
easily shown by appropriate staining reagents. It is 
situated eccentrically, at the edge of the entoplasm, 
and appears as a discoid body, about 6y in diameter, 
with a sharp contour, which, though occasionally 
broken and irregular, is generally even; it may be 
distinguished from vacuoles of the same size by its 
higher refracting power. A nucleolus can seldom be 
observed, and in stained specimens only. 
Foreign bodies are frequently seen in the amcebe, 
especially red blood-cells. These are sometimes so 
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