78 
Proceedings of the Royal Irish Academy. 
of our form, as well as having made an endeavour in the figures, by the 
aid of the brush, to realize its likeness, I trust I shall have succeeded 
in conveying to observers a fair and available representation of this 
rhizopod, in some of the somewhat varied aspects of its living condi- 
tion. I must, however, devote a few words to a record of how far the 
behaviour of this rhizopod, under the action of certain re-agents, bears 
out or explains the preceding account of its structure, and then speak 
of its seeming affinities, and assign it to its genus. 
On the application of Beale's carmine fluid, a collapse of the whole 
form, coat and all, takes place ; the green granules become more glassy 
in appearance ; soon the whole, coat and all, begins to swell out again 
as globular as before ; no retraction of the sarcode body-mass from the 
coat seems to ensue, nor any dissolution of the hair-like external pro- 
cesses. The body-mass by-and-by become'^ granular in appearance, 
and far less hyaline. Eut the most important elfect produced by this 
valuable re-agent, is the unfailing certainty with which it brings to 
view the ''nucleus," by reason of the extent to which this body 
absorbs the carmine colour, imtil by-and-by it assumes an intense red 
colour, far in excess of the pale rose tint presented by the remainder 
of the sarcode -mass. The nucleus appears as before, mostly slightly 
longer than broad, and sharply bounded. Sometimes a second rather 
sharp outline is apparent a little within the outer one ; the former of 
which, when present, bounds a space more highly coloured than the 
border beyond it. This, however, appears to be exceptional, and 
although in the living condition the nucleus appears evenly granular, 
its substance now appears smooth and homogeneous. This experi- 
ment then is very satisfactory, as disclosing the presumably constant 
"nucleus," but it does not seem to demonstrate the body-mass and 
its outer investing coat as independent structures ; for, altered in ap- 
pearance as may be the former, and though some of the granular 
contents, and even some basic sarcode may become extruded, the body- 
mass and the coat still seem to remain closely applied to each other. 
The application of acetic acid does not seem to produce any very 
noteworthy effect, save rendering the outline of the nucleus more 
sharp and marked. IS'o very evident contraction of the body-mass from 
the coat took place. But this experiment I have not tried sufficiently 
often to rely very much upon its general results ; and I imagine I did 
not succeed in bringing this reagent to bear with sufficient energy. 
The use of a re-agent I happened to have by me for another purpose, 
a weak solution of iodine and iodide of potassium, was attended with 
very pretty results. This reagent, vigorously applied, caused an 
immediate contraction, or rather coagulation, of the sarcode body- 
mass into one or several balls, the whole coming clean away from the 
outer mantle or coat ; when allowed to act more slowly, the result of 
the gradual retraction of the body-mass as above can be seen. If, in- 
deed, the finding of empty coats (see Fig. 4) in the material did not 
already prove the independent character of this investment, I mean 
its want of organic union with, that is, its being no mere condensed 
