THE MICROSCOPE AND ITS REVELATIONS. 



FIG. 282. 



Rhizopods to be presently described, is another simple Protozoon discovered 

 in ponds in Germany by M-M. Claparede and Lachmann, and named by 

 them Lielerkuhnia Wageneri. 1 The whole substance of the body of this 

 animal and its pseudopodial extensions (Fig. 282) is composed of a homo- 

 geneous, semifluid, granular protoplasm; the particles of which, when 

 the animal is in a state of activity, are continually performing a circula- 

 tory movement, which may be likened to the rotation of the particles in 

 the protoplasmic network within the cell of a Tradescantia ( 355). It is 

 a marked peculiarity of the pseudopodial extension of this type, that it 

 does not take place by radiation from all parts of the body indifferently; 



but that it proceeds entirely from a sort 

 of trunk that soon divides into branches, 

 which, again, speedily multiply by further 

 subdivision, until at last a multitude of 

 finer and yet finer threads are spun-out, 

 by whose continual inosculations a com- 

 plicated network is produced, which may 

 be likened to an animated Spider's web. 

 The entire absence of anything like a 

 membranous envelope is clearly evidenced 

 by the readiness with which the subdivi- 

 sion and the coalescence of the pseudo- 

 podia alike take place. Any small ali- 

 mentary particles that may come into con- 

 tact with the glutinous surface of the 

 pseudopodia, are retained in adhesion by 

 it, and speedily partake of the general 

 movement going-on in their substance. 

 This movement takes place in two prin- 

 cipal directions; from the body towards 

 the extremities of the pseudopodia, and 

 from these extremities back to to the body 

 again. In the larger branches a double 

 current may be seen, two streams passing at the same time in opposite direc- 

 tions; but in the finest filaments the current is single, and a granule may be 

 seen to move in one of them to its very extremity, and then to return, per- 

 haps meeting and carrying back with it a granule that was seen advancing 

 in the opposite direction. Even in the broader processes, granules are 

 sometimes observed to come to a stand, to oscillate for a time, and then 

 to take a retrograde course, as if they had been entangled in the opposing 

 current, just as often is to be seen in Cham. When .a granule arrives 

 at a point where a filament bifurcates, it is often arrested for a time, 

 until drawn into one or the other current; and when carried across one of 



LieberTcuhnia Wageneri. 



1 "Etudes sur les Infusoires et les Rhizopods;" Geneva, 1850-1861. The beauti- 

 ful figure of Lieberkuhnia, given by M. Claparede, has been reproduced by the 

 Author in Plate 1 of his ' Introduction to the Study of the Foraminifera.' A Rhizo- 

 pod of the same type has been discovered by Mr. Siddall (of Chester) in Sea- water 

 from the North and South Coasts of Wales, which he regards as especially identi- 

 cal with L. Wageneri ("Quart. Microsc. Journ.," N. S., Vol. xx., p. 144), but which 

 the Author (who has great confidence in the accuracy of the excellent observers 

 by whom the latter was described) must regard as differentiated from it (1) by the 

 existence of a pellucid flexible investment (foreshadowing the ' test ' of Gromia), 

 having a definite orifice bordered by four infolded lips, through which the sarco- 

 dic trunk issues forth ; and (2) by the presence of a number of highly refractive, 

 short, rod-like spicules set at various angles on the external surface. 



