104 BRITISH FRESHWATER RHIZOPODA. 



frequently appearing as an ovoid or double-convex 

 elongated body, narrowed at the extremities, each 

 extremity being furnished with a bundle of short, 

 capitate, pseudopodal filaments, with other simple ones 

 intermixed. One or more filamentous pseudopodia 

 are usually to be seen projecting from the body-surface, 

 but these are inconstant, appearing and disappearing 

 at various points. Not infrequently the entire body 

 becomes remarkably elongated, when it appears as 

 though a long, tapering pseudopodium had been thrust 

 out posteriorly (PL XI, figs. 8, 11) whilst the anterior 

 plasma expands and takes a fan-shaped outline, clothed 

 with pseudopodal filaments of varying length, the 

 shorter ones mostly capitate. The posterior prolonga- 

 tion is induced by the adhesion of the plasma-body, 

 at a point on the convex surface, to some foreign 

 object (or to the glass slip over which it is moving) 

 whilst the forward movement is continued, the body 

 posteriorly thus becoming more and more attenuated, 

 smooth throughout, and terminating in a sharp point. 

 The food of the animal consists of minute diatoms. 

 Like the preceding species it is destitute of contractile 

 vacuole, and apparently also (so far as has been 

 observed) of nucleus. Its life-history is unknown, 

 though it may be presumed to be analogous to that of 

 V. voraXj with which it is most nearly allied. 



Dimensions : Length of the ovoid body 60-70 /x ; 

 average breadth 20-30 p.. When elongated, measuring 

 from the convex face to the posterior extremity, 110 /A, 

 or more. 



In water from a sluggish stream near Barking, 

 Essex, amongst Conferva?, etc., May, 1901. 



V. flabellata may be distinguished from V. vorax by 

 its paler colour, and also by its peculiar movements. 

 It is very active, and its pseudopodal changes are 

 unceasing. The examples which furnished the above 

 description (and which were kept under observation 

 for a considerable time) had little or none of the red 



