THE MOVEMENTS AND REACTIONS OF AMCEBA. 



155 



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

 It then moved rapidly forward, occupying successively the positions 

 indicated by the line of circles in ^. (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 (^, //). 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 (//, i.j')- It is 



Fig. 49.* 



possible that as the tip became very slender its distance from x 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 X ; 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 x. 



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 Amoeba in 

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

 dium at the anterior end. For explanation see text. 



