ARCHER—ON RHIZOPODA. 261 
For some time I imagined, as I now believe erroneously, that these 
forms might fall under the genus propounded by Schlumberger*— 
Pseudodiflugia—but that type is described as having a membranous 
test; which, so far as I can see, would exclude the present forms. [ 
would be disposed to suggest that Pseudodifflugia (Schlumb.) might 
really come nearer such a form as the so-called Gromia Dujardinii 
(Schultze). 
Further, it appears to me that these differ in character quite from the 
pseudopodia of Kuglypha or Cyphoderia, not to speak of the completely 
distinct kind of test. In these genera and their allies the pseudopodia 
are few, unbranched, extremely slender, and very lively, thrown out 
comparatively rapidly, sometimes waved with no little vigour, drawn 
in hurriedly, often showing a knob-like expansion or clavate end during 
the act—all quite unlike the inert, comparatively persistent, shrub-like 
tuft of thicker pseudopodia shown by our forms. I think those 
who may be inclined to consider the importance here attributed 
to the kind of pseudopodia, and their appearance and behaviour, as too 
overdrawn, would at least be obliged to admit, on looking over these 
forms in a living state upon a slide for a length of time, that they possess 
at least remarkable idiosyncrasies. 
The form shown in PI. X., fig. 1, is, I think, not uncommon; but 
it is easy to pass it over, though, as will be seen, by no means minute, 
as it may be taken almost for a pellet of some kind of excrementitious 
matter, and, moreover, it is shy of protruding its pseudopodia. The 
test, as mentioned, formed of a number of elongate and granular particles 
agelutinated by an intervening brownish substance, sometimes presents 
itself of an irregular, or lobed, or distorted shape, though a broad ellip- 
tic figure seems to be more usual; in so far as this goes, it is further 
against its presumed identity with Pleurophrys spherica. The body of 
the creature is suspended within this test, from which it mostly stands 
off anotable distance, and it is granular. I have not noticed a vacuole, 
but a large orbicular nucleus is often readily to be perceived, which by 
some management can be extruded intact. 
The form represented by fig. 2 (Pl. ? amphitremoides) is much 
smaller, and prone to cover itself with various diatomaceous frustules, 
and in the specimens that I have met with contained numerous chloro- 
phyll granules, but I could not see anucleus. The ramifications of the 
pseudopodia seem more copious as compared with the preceding, hence 
the tuft appears more shrub-like. A smaller and nearly orbicular form, 
seemingly the same, is met with without diatomaceous frustules, but 
covered by large arenaceous particles—this perhaps, after all, equally 
likely to be the same as Pl. spherica (Clap. et Lachm.) 
The third form, which I have named from its colour Plewrophrys 
fulwa, is far smaller than either of the preceding, and 1s characterized by 
its tawny hue and the pellucid character of its rough test, owing to its 
* «¢ Annales des Sciences Naturelles,’’ 3rd Ser., tom. lli., p. 256. 
