224 ME. J. CASH OK NEW AND LITTLE-KNOWN 



but all the individuals met with had the features described 

 suflficiently well-marked. One was observed to be feeding on. a 

 species of rotifer, which was very plentiful in the same 

 gathering. During the inception of one of these the body of 

 the Penardia underwent considerable changes ; it became 

 congested and opaque, and the unoccupied pseudopodia, where 

 not "withdrawn into the general mass, were comparatively inert. 

 After feeding, the animal would remain stationary, or with very 

 little movement, usually for a considerable time. 



Order YAMPTEELLIDA. 

 Grenus Vampyeella, GienkowsTcy. 



Vampteella elabellata, sp. nov. (PL 26. figs. 5, 6.) 



Plasmodium very mobile, most frequently appearing as an 

 ovoid or double convex elongated body, narrowed at the ex- 

 tremities, each extremity furnished with short pseudopodal 

 filaments, mostly capitate. A few fine, elongated, straight (but 

 inconstant) pseudopodia are sometimes projected from the body- 

 surface. Not unfrequently the entire organism becomes re- 

 markably elongated, as though a tapering pseudopodium had 

 been thrust out from one side (fig. 6). This is induced by the 

 adhesion of the plasma to some foreign object, whilst the 

 animal continues its forward movement, the effect being to draw 

 it out to a fine point, the frontal outline meanwhile becoming 

 fan-shaped, and fringed with short capitate rays, with which a 

 few longer and finer non-capitate filaments are intermixed. In 

 all the examples met with the body was pale, with little or none 

 of the reddish colour characteristic of the VampyrellcB. 



Dimensions : length of the ovoid body 60-70 yu ; average 

 breadth about 20 fx. Length when elongated, from the convex 

 frontal margin to the pointed extremity, 100 /x or over. 



In a broad and sluggish stream crossed by the Barking and 

 Purfleet highway, about a mile from Barking, Essex, associated 

 witb Difflugiella, &c., amongst surface-vegetation : Aug. 1901. 



Order CONCHULINA. 



Pamily Aecellida. 

 Grenus Diffltjghella, gen. nov. 

 Test ovoid ; in transverse section circular, composed of 

 chitinous transparent membrane j the body-protoplasm usually 



