THE MOVEMENTS AND REACTIONS OF AMCEBA. 



forward very slowly (c, d, e) till at f it passed to the upper surface. 

 It then moved rapidly forward, occupying successively the positions 

 indicated by the line of circles in g. (The Amoeba itself was, of course, 

 progressing ; no attempt is made in the diagram to represent its change 

 of position. ) Finally the particle x had nearly reached the anterior 

 end, when the latter forked, sending two pseudopodia upward and 

 forward into the water ( g', h). The particle x was at first at the base 

 of the right pseudopodium. This was now projected forward as a very 

 long, slender pseudopodium bearing the particle x. The latter was 

 carried steadily out from the body, maintaining almost exactly its 

 original distance from the tip of the pseudopodium (/, /,_/). It is 



FIG. 49.* 



possible that as the tip became very slender its distance from .v became 

 slightly greater as if, by a circular contraction of the intervening part, 

 the tip were forced further out ; but there was no movement backward 

 of ,v; on the contrary, it moved steadily forward, its distance from the 

 base of the pseudopodium continually increasing. Unfortunately at 

 this point the animal passed under a mass of debris, so that I was 

 unable to trace further the history of that point on the body surface 

 marked by the particle .v. 



I have, altogether, about a dozen observations showing this outward 

 movement of particles on the surface of free pseudopodia. The three 



* FIG 49. Movements of a particle (x) attached to the surface of Amaba in 

 passing from a pseudopodium at the posterior end over the body to a pseudopo- 

 dium at the anterior end. For explanation see text. 



