8 



botant. 



The formation of tlie new current may be explained as followht 



Let A B be a sireiim in which the movement is from A 



toiJ; clearly there will be an aggregation of protoplasm about B. 

 When the current in the direction A B stops, the new one, in the 

 1-everse direction, B A, begins at A, by the movement toward it of the 

 particles nearest to it ; next the particles further oflF move toward A ; 

 after this, those still further ofE, and so on. The current extends lack- 

 ward. So, too, when a stream begins de novo, it is propagated back' 

 ward from tlie point of beginning. 



8.— Mass-Movement (AmcBtaa-Movement). In the flowing 



back and forth in the 

 streams the movement 

 may be greater in one 

 direction than in the 

 other ; this causes a 

 slow motion of the 

 , whole Plasmodium in 

 the direction of 

 the greatest movement. 

 When this takes place 

 in the case of streams 

 which begin in the mar- 

 gin of the Plasmodium, 

 protuberances of vari- 

 ous shapes arise ; these 

 may be extended into 

 branches {pseudopo- 

 dia), which may again 

 be branched one or 



Pig. 6. -Otitline of a Plasmodium of Z)j(Jj/»iiMm ^°^^ timeS. By the 

 8c?j7M/o forming pseudopodia The heavy Ijlaclc anastomOsinST of thcsC 

 line indicates the outlme at tbe beginning ot the o 



observation ; the psendopodium a-b formed in 8 branches 

 seconds, c-d in 30, and c-e in 55 seconds. X 10. 

 —After Hofmeister. movmg and 



network is formed. 



a 



complex 

 changing 

 (See Fig. 140, page 208) There is pos- 

 sibly to be separated from the above-described mass-move- 

 ment that more or less rapid change of external contour 

 which has, from its resemblance to the motions of the 

 Amoeba, been denominated the Amoeba-movement (Fig. 6). 

 It is best observed in the so-called "Amoeba-form " stage of 

 *he swarm-spores of the Mvxomycetes. 



