HANDBOOK OF INVERTEBRATE ZOOLOGY. 



Place the slide upon the stage of the microscope, and 

 examine it with a magnifying power of two hundred or 

 three hundred diameters. If careful examination leads to 

 the discovery of no amu-ba 1 , examine the oo/e from another 

 locality in the same way. It is extremely difficult to tell 

 a beginner exactly what to search for. If the student is 

 working under guidance, the instructor should find an 

 amoeba, and after the student has had an opportunity to 

 see it he may hunt for others. If Avorking alone, the 

 student should read the following description, 'and then 

 hunt for an object which agrees with it. 



Having found an amoeba, note : 



I. The irregular, granular, nearly colorless body, which 

 is made up of an ill-defined central portion (Fig. 1, a), and 

 a variable number of irregular processes, the pseudopodia 

 (Fig. 1, b). The body may be nearly spherical and the 

 pseudopodia small, or the body may be almost absent and 

 the pseudopodia large, and the animal may pass through 

 all the intermediate stages between these tAvo forms in a 

 feAV minutes, or it may remain without change for several 

 minutes, especially if it has just been transferred to the 

 slide. The very much branched forms, like the one 

 figured, are most common in a drop which has been for 

 some time on the slide undisturbed. 



II. The body consists of a pale, nearly colorless, jelly- 

 like substance, the sarcode, in which tAvo layers AA'ill be 

 recognized. 



a. The outer layer or ectosarc (Fig. 1, c) forms a trans- 

 parent, very slightly granular film over the entire surface. 



b. The darker, more granular eit< Injure fills the interior 

 of the body and extends into the pseudopodia. It con- 

 tains many bodies, which will be noticed later. There is 

 no abrupt line betAveen the ectosarc and endosarc. 



