AMCEBA PROTEUS 



take up a fixed position from which they do not toove. 

 The nature of the problem before us will, however, be 

 better appreciated if we make a study of some of the 

 lower organisms. 



In Fig. 1 we have a drawing which represents that 

 remarkable organism known as Amoeba proteus as seen 

 under a fairly high power of the microscope. Specimens 

 may be found on the surface of mud on the bottom of 

 fresh-water ponds or pools. 

 To the naked eye they are 

 mere specks, for they are 

 seldom more than -^ inch in 

 diameter. We place a drop 

 of water containing one or 

 more of these specks on 

 a glass slip, and, having 

 covered the drop with a 

 thin cover - glass, proceed 

 to microscopic examination. 

 At first we experience some 

 difficulty in locating our 

 interesting subject, because, 

 owing to the disturbance of 

 the even tenor of its way, 



it is quiescent and hardly distinguishable among the fine 

 particles of debris scattered in the thin film of water. In a 

 short time, however, we shall observe signs of movement, 

 and be able to note several interesting details. Amoeba is 

 a speck of protoplasm of no definite form, yet capable of 

 assuming many forms, in which respect it is thoroughly 

 protean and altogether worthy of its specific name. 

 Under a magnification of, say, 250 diameters, the main 



Fig. 1 Am(eba Proteus. 



C.V., Contractile vacuole; n, nucleus. 



