in the Pseudopodia of the Rhizopoda. 407 



The so-called Granular Movement. 



With regard to the appearances hitherto known under which 

 the granular movement occurs^ I must here give the following 

 indications. Dujardin speaks only of an ebb and flow of body- 

 substance containing globules, in consequence of which the 

 filaments appear uneven and granular. Max Schultze, however, 

 represents the ebbing and flowing mass as advancing partly in, 

 but especially on, the filaments as an apparent granule which 

 contains the larger globules. J. Miiller indicates that an inter- 

 nal granular movement, like that in the rays of Adinophrys, 

 does not occur in the pseudopodia — that here the granular 

 movement rather resembles a granule advancing on the surface 

 of the filament; and he adds the observation that mucous 

 globules and foreign bodies are also moved to and fro by the 

 granules. In his memoir (p. 7) we also find the following re- 

 markable passage : — " Not unfrequently the filaments are seen 

 to be thickened or swelled here and there, and this elongated 

 swelling (little knot) is seen to advance upon the rays like the 

 granules, which may be referred either to a progressive contrac- 

 tion or to elongation and shortening, but is perhaps connected 

 with the granular current.^' These words are only thrown out 

 doubtfully, and are not again referred to on other occasions 

 when the movements of the pseudopodia are spoken of; never- 

 theless they contain an observation which, by further investiga- 

 tion of the phenomena, must have led J. Miiller to the same 

 conception of the granular movement as that which I have 

 arrived at by my investigations. 



The animal in which I first observed the granular movements 

 exhibited them only on particular filaments, and there were 

 even moments in which the visible extended pseudopodia were 

 quite quiescent. The granular movement appeared to be, as 

 described by Max Schultze and J. Miiller, an apparent grain or 

 granule moving to and fro on the surface of the filament. I 

 must add, however, that the movement of the granule was not 

 uniform, but that it appeared to jump forward over the surface, 

 or, at least, showed a tremulous movement. But it struck me 

 as very remarkable that, notwithstanding numerous supposed 

 affluxes of granules, and although it is common enough to see 

 that the quiescent granule at the extremity of the filaments does 

 not return, not a single perceptible quiescent globule could be 

 detected in the entire field of vision, either in the surrounding 

 fluid or in or on the substance of the rays themselves. And yet 

 the sarcode-substance flowing out of the body to the rays should 

 contain globules, and the larger globules should not only efi*ect 

 the protrusion of the flowing mass above the level of the fila- 



