AMCEBA COLL 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 amoeba. 



The entoplasma constitutes the greater portion of the 

 body of the amoeba, being usually centrally situated, 

 but occasionally slightly eccentric. In the smaller 

 forms of amoebae 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 edoplasma is quite homogeneous, forming a zone 

 of variable thickness around the entoplasrn. It has 

 the appearance of finely ground glass of a distinctly 

 pale green tint. 



In most amoebae a nucleus can be seen. Its detection 

 is not always possible in fresh or motile amoebae, but 

 under certain conditions in the motionless or dead 

 amoebae 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 6// 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 amoebae, 

 especially red blood-cells. These are sometimes so 



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