26 ECONOMIC ZOOLOGY AND ENTOMOLOGY 



Using the higher power lenses it will be seen that the outer part 

 of the jelly-like body, called ectosarc, is clearer than the more 

 granular inner part, the endosarc, and that within the endosarc 

 are many small granules, the food particles, and a compara- 

 tively large, round, clear space, the contractile vacuole, which 



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' > - i' -JaHt \ V^ . 



, . - f?Z;*v* :.;' ; 

 J v^t ' ' *-.'/ < 



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FIG. 8. Amoeba sp. Showing the forms assumed by single individual in 

 four successive changes. (Greatly magnified; from life.) 



appears and disappears with more or less regularity. Some- 

 times the darker, denser nucleus can be seen in the living 

 Amoebae, but it shows much more distinctly in specimens 

 killed by allowing a little carmine or other staining fluid to 

 run under the cover-glass. 



Active Amoebae are constantly changing their shape, and by 



