22 ELEMENTARY BIOLOGY. [ill. 



4. Movements : 



a. Watch the process of formation of a pseudopodium. 

 A hyaUne elevation at first ; then, as it increases 

 in size, currents carrying grannies flow into it. 



h. Locomotion : watch the process, — a pseudopodium 

 is thrown out, and then the rest of the body 

 is gradually drawn up to it. 



c. If the opportunity presents itself watch the pro- 

 cess of the ingestion of solid matters. 



d. [Observe the movements on the hot stage ; wai-mtli 

 at first accelerates the movements, but as the tem- 

 perature approaches 40° C they cease, and the whole 

 mass remains as a motionless sphere.] 



e. [Effects of electrical shocks on the movements.] 



5. Mechanical Analysis : crush. The whole collapses, ex- 

 cept sometimes the nucleus, and even that after a time 

 disappears : there is no trace of a distinct resisting 

 outer sac. 



C. Chemical Analysis: Treat with magenta and iodine. 

 The whole stains, and there is no unstained enveloping 

 sac. Iodine as a rule produces no blue coloration ; 

 when blue specks become visible it is probable that 

 the starch which they indicate has been swallowed. 



7. [Look for encysted specimens : and for specimens which 

 are undergoing fission.] 



8. Another form of Amoeba is not unfrequently found 

 which differs from that just described in being much 

 le.ss coarsely granular, and in having no well-defined 

 ectosarc and endosarc, and also in having much longer, 

 more slender and pointed pseudopodia. 



