11] 
erasies of one “ sarcode” as compared with another “ sar- 
code,” or, very probably better, definite patches of ‘* bioplasm” 
(Beale), I need hardly say I refer now to such as is presented 
by Rhizopoda only, and in referring to Rhizopoda, I refer to 
freshwater Rhizopoda only. ‘“Sarcode” plays a part in 
higher beings subserving to more exalted ends, but I refer to 
that which meets our attention in the pools to which my own 
experience is confined. If, indeed, I were acquainted with 
marine rhizopodous forms, I might possibly be of a different 
view in respect to them, from that I feel as yet. constrained 
to hold as regards their freshwater relatives. Of course, I 
do not pretend to aver that some of the more minute forms 
we now and then encounter may not be young or transitory 
or undeveloped states of certain others, but this would not, 
I imagine, greatly militate against the general correctness of 
the view for which I here contend; neither do I aver that 
the various forms we from time to time meet with are immu- 
table or not subject to a certain amount of modification. I 
would only venture to urge that such does not appear to be 
by any means so great as some would hold. Ido not now 
dwell on the fact of “ zygosis” taking place uniformly like 
form with like form; whatever may be the significance of 
that phenomenon, it is at least one which I have noticed 
myself in nearly every form of all the genera, each indi- 
vidual species always conjugating only with its own fellow. 
Nor does a certain amount of difficulty in identifying even 
some common forms with some of the older authors’ descrip- 
tions or figures argue materially, if at all, against my view ; 
for, as I would as yet rather venture to think, such difficulty 
may be attributable, not so much to the deviation of any 
particular form in question from the author’s “ species,” 
which he may have had before him, as to the original want 
of completeness in seizing the details and want of conformity 
of the author’s “‘ description,” or figure to nature’s “‘ species,” 
if I may rightly here use the term—due, perhaps, in great 
part to the fact that Nature is so chary in giving us more 
than glimpses of her doings, and all that the author saw was 
but a single aspect or only a few of the features of a form of 
existence, the rest of which, it might be, on that occasion, 
were screened and hidden from his ken. 
Hence I imagine that descriptions of these forms cannot 
be too minute or too much in detail. If such be as carefully 
and as closely as possible carried out, and figures made as 
painstakingly as possible, and examples afterwards found 
cannot be identified therewith, then that form must present 
yarious aspects or phases, and on the next occasion the varia- 
