Archer — On Freshwater Bhizopoda. 
99 
or less, thongh. but slightly, longer than broad, that is, broadly- elliptic. 
The body suspended within has the faintly granular aspect and some- 
what palish-blue hue of that of Diplophrys itself, and the same larger or 
smaller orange or amber-coloured shiny oil-globule — this oil-globule, 
not always uniform in shade, sometimes a reddish-orange at one side 
passing off into a greenish-yellow at the other. This form occurs of 
various sizes. It has never yet shown any pseudopodia or other ex- 
ternal portion of structure, nor any movement. It is widely distri- 
buted in this country, though not abundantly present in any gather- 
ing made ; nor, indeed, is it often encountered, which, however, may 
be due rather to its very minute size causing it to be overlooked ; it is, 
however, more frequently seen than Diplophrys, though the latter 
sometimes occurs more numerously in a gathering than the former 
seems ever to do. A curious question arises as to when or how this 
puzzling organism, so inert, as it appears, can collect and pose the 
heterogeneous foreign bodies forming the nest " in which it becomes 
embosomed. 
In thus once more drawing attention to the forms immediately in 
question, in this additional note thereupon, I do not suppose the sub- 
ject is by any means disposed of or exhausted ; it is quite possible that, 
by good fortune, some new or unexpected features in connexion with 
them may become revealed. Should such occur to myself, I trust I 
might be once more borne with in reviving allusion to Acmithocystis 
spinifera or its allies. Should such occur to others, I should hail with 
a lively interest a record of their observations. 
Plagiophrys sphcerica (Clap, et Lachm.). 
In the course of this and my preceding communication, I have 
sometimes made allusion to the form which I am inclined to believe 
must be identical with Plagiophrys sphcerica (Clap, et Lachmann) 
it is, at all events, one which now and again sparingly presents itself 
from various localities. If, however, I am quite correct in this iden- 
tification of the rhizopod I have had in view, it has struck me that the 
figure (loc. cit.) is not sufficiently graphic ; still, had I not lately met 
with some examples, not altogether coinciding with that which I had 
previously known, and which, for the present at least, I must continue to 
regard as Claparede and Lachmann' s species, I would not (as yet at 
least) have thought it desirable to attempt a drawing of the form. Eut, 
though certain specimens lately taken present some distinctions from 
the former, and on that account it has appeared to me to be perhaps 
worth while to endeavour to convey a likeness of both, I am, however, 
not as yet sufficiently satisfied that these are truly two distinct rhizo- 
pods, and I content myself with simply submitting the di^awings to 
the notice of other observers whose experience may assist in throwing 
a light on the question. 
* Claparede and Lachmann: "Etudes sur les Infusoires et les Rhizopodes." 
P. 454, PI. xxii., Fig. 2. 
