Archer — On Freshivater Rhizopoda, 
93 
although there is, so far as I can see as yet, no evidence that, though 
to a certain extent so very like, it actually has anything to say to 
that form, and still less to Acantliocystis spinifera, nor have I, indeed, 
any thing to add to the crude record I have already given of it. 
I must now own that I ought to have put forward the statement, 
that Acantliocystis spinifera (Greeff ) did not occur with us, in at least a 
more qualified manner, for I was then, and have long heen, acquainted 
with what I now feel very well satisfied is no other, the yellow glo- 
bules, however, not present, and varying comparatively a good deal in 
dimensions. But it was not until subsequent to my previous communica- 
tion having been published, that I met with fully characteristic examples, 
confirming Greeff's description, so far as relates to the form itself, in all 
particulars — the well-marked outline of the presumed ''central capsule" 
— the numerous yellow globules immersed in the body-mass, but exterior 
to the ''capsule" — their occasional extrusion through openings made by 
the temporary displacement of the long, and fine, and slender equal-sized 
pointed radial " spines" — in fact, all the described characteristics pre- 
sented themselves to observation. The examples previously met with 
by me I now regard as simply smaller, and probably young states of 
one and the same form, the "capsule" not yet formed nor yellow 
globules present — or indeed these, perhaps, but few or faint in colour ; 
in fact, Greeff himself states, these do not always occur. Such ex- 
amples I had, indeed, before me in my "mind's eye" when I wrote, but 
kept a mention of them in abeyance, imagining they might probably 
be younger states of Acantliocystis turfacea (Carter), and required 
further observation. It is true the spines here are difi'erent from what 
is characteristic of that species, but it struck me they might, by fresh 
accretion, eventually assume their ultimate varied lengths and bifid 
apices. I admit such an assumption was gratuitous, the more espe- 
cially after a perusal of Greeff's memoir, and due consideration of the 
characteristics of his A . spinifera. 
I have now, however, no hesitation in recording this form [A. spi- 
nifera, Greeff ) as occurring in this country ; for, besides the more 
minute forms alluded to I have lately taken a number of perfectly 
typical examples from both County Westmeath and County Tipperary. 
Of the smaller forms I have tried to re-produce an example in Fig. 8, 
to which I shall presently advert, first drawing attention to the fea- 
tures illustrated by Pig.- 7, representing a preparation after treatment 
in Beale's carmine fluid. 
Amongst the points illustrated by the example before us (Fig. 7), 
the first that may probably attract notice is the fact that we have here 
two individuals in a state of "zygosis." This phenomenon is occa- 
sionally seen in all Ehizopoda, but is, perhaps, more noteworthy in those 
" E-adiolarian" forms, like the species of Acanthocystis, which, unlike 
those of "Amoeban" afiinity, are altogether surrounded by a kind of 
wall of solid parts (spicula) which might be supposed to interfere 
with, or act as a bar or hindrance to, the mutual fusion of the sarcode 
bodies. However, not only the present form, but likewise Acantlio- 
