VAMPYRELLA LATERITIA. 97 
elongated and filamentous pseudopodia, and intermixed 
with them a variable number of shorter and stouter 
capitate processes which elongate and contract inces- 
santly. Wawve-like or lobate expansions of clear 
ectoplasm, and sometimes also digitate processes, are 
frequently emitted from the periphery. No nucleus 
of the normal type has been detected in this species, 
but Zopf demonstrated the presence of scattered grains 
of nuclear substance. The animal is stated by most 
observers to be destitute of a contractile vacuole, but 
in some states (probably young) one, if not more, is 
undoubtedly present, though obscured more or less by 
the brick-red contents of the plasma-body. The. 
chlorophyl of filamentous algz seems to form the sole 
food of V. lateritia, but the animal does not confine 
itself to any particular species. It glides through 
the water with a motion similar to, but more rapid 
than, that of Actinophrys, and on coming in contact 
with an alga-filament will often travel along it and 
sometimes break it at the joints, or pierce the indi- 
vidual cell, in order to extract the chlorophyl. 
Dimensions variable, averaging 30-40: in diameter. 
In shallow bog-pools, amongst wet Sphagnum, and 
occasionally in ponds and ditches amongst Conferve. 
Not infrequent in Cheshire, associated with Acantho- 
cistis, etc.; and in Epping Forest. Near Brigg, 
Lincolnshire; Harris, Outer Hebrides (G. S. West). 
The habits of this species make it one of the most 
interesting of the tribe. The Rhizopoda, as a rule, feed 
on such things as fall in their way. They are gleaners 
merely. Vaimpyrella lateritia, on the contrary, seems 
to hunt for its food, and has, in a very humble degree, 
a power of selection. Once found, a filament of Spzro- 
gyra, or other allied alga, is taken possession of by 
the Vampyrella, and not given up until the animal’s 
needs are satisfied, when it usually passes into an 
inert or resting state in which it will remain for an 
indefinite period. Its method of attacking a filament 
7 
