149 
in our rhizopod a minute globular body, with at least slender 
pseudopodia, emanating in one bundle from a single little 
depression (or “boule,” Clap. and Lachm.) at one side, and 
with an integument, which might, perhaps, when seen only 
in the living example, appear only as a “‘ skin” (fig. 11), and 
thus, at all events, to a considerable extent falling in with the 
authors’ description of their form. 
But when our form is treated with acetic acid the body 
completely retracts from the integument, and it is shown as 
an independent, colourless, and smooth coat or case, or—may 
we call it—“ test”’? (see fig. 12), thus proving a characteristic 
not claimed for their forms, at least to this extent, by Cla- 
paréde and Lachmann, something more, in fact, than what 
would, I think, be called a mere “ skin.” Might not our forms, 
indeed, be designated as “ cuirassés”’ ? 
But to advert, then, to the mutual differences presented by 
the examples lately met with by me (fig. 14), as compared 
with the form here designated Plagiophrys spherica (fig. 11). 
I found it impossible to attain a good profile view of one of 
the former, so, like Claparéde and Lachmann themselves, in 
this instance, [ have been obliged to be content with a figure 
drawn from the posterior aspect. Comparing, then, the form 
we are the more familiar with (fig. 11) with that more 
recently met with (fig. 14), we see the colour of the bédy, or 
rather contents, is much darker in the latter (fig. 14) ; this, 
indeed, is probably of but little moment ; the wall or exterior 
appears even thinner, smoother, sharper, more glossy. We 
see, too, the pseudopodia far more conspicuous, longer, here 
and there more broadened out, granuliferous, more fitful and 
changeable, and, so to say, of a more solid character, less 
hyaline ; but all this, it may be, requiring far more observa- 
tion to decide as to its being specially characteristic of truly 
distinct forms. ‘The differences under the action of Beale’s 
fluid are more tangible. Specimens of the rhizopod repre- 
sented by fig. 14, upon being treated with this reagent, 
immediately collapsed, and assumed the crumpled appearance 
indicated by the outline shown by fig. 15. In afew minutes 
this crumpled form began to expand, and speedily the folds 
all became obliterated, and the whole inflated, until a balloon 
shape was assumed (fig. 16). After a time some of the sar- 
code-mass became expelled through a rather wide truncate 
neck-like anterior extremity, and the body-mass became dis- 
tinctly retracted from the outer case (test ?) ; the nucleus took 
a bright red colour. Sometimes, but by no means in every 
_ instance, there was to be seen a brighter, smaller, “ nucleolus- 
like” (?) -dot within. In the instance figured a couple of 
