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yellow oil-like globules presented themselves, very like the 
yellow globules of Acanthocystis spinifera (Greeff), and, in my 
opinion, seemingly largely going to prove that in that form 
these cannot be at all properly regarded as homologous with 
“yellow cells.” The other specimens (fig. 11), those of the 
presumed Plag. spherica, also treated with the carmine fluid, 
behaved somewhat differently. Nocollapse or crumpling up 
of the total rhizopod took place; on the contrary, rather by 
degrees a slight expansion. Nor was it for a very consider- 
able time, comparatively, that the nucleus took its dye 
completely, nor was there any apparent retraction of the 
body-mass from the outer envelope, nor did the latter become 
balloon shaped, but its anterior border assumed a very 
broadly conical figure, no very evident apical opening offer- 
ing itself to view. But that there is, and, indeed, as a matter 
of course, must be, such an opening, is shown by the specimen 
treated with acetic acid (fig. 12); for here the contents, be- 
coming retracted, are partially extruded, and even the nucleus 
expelled through the rather minute aperture at the apex, this 
frontal region assuming an appearance showing two trans- 
verse annular folds, giving a zigzag lateral outline. It ist his 
portion which, in both examples, in the living state, is pushed 
inwards, giving the depressed and folded appearance then 
seen—the “‘ boule” of Claparéde and Lachmann. The ante- 
rior opening therein, indicated in fig. 12, though seemingly 
so very small, must, however, be of considerable power of 
expansion to allow the entrance of so comparatively large an 
object as that shown within the specimen represented by 
fig. 11, which presents an example of Cosmarium cucurbita 
incepted as food. 
All this, then, seems to evidence that there must be attri- 
buted to these beings more than a skin—a distinct and 
separable ¢est—and this would bring the’ forms very close to 
Euglypha and Trinema in a generic point of view ; and, in 
fact, the widest distinction is the facetted test of the forms 
appertaining to those genera, and the absolutely smooth one 
here ; moreover, the behaviour of the pseudopodia is not alike 
in those. In a specific point of view, be these two, here 
drawn attention to, really mutually distinct or not, which I 
leave an open question, I need not urge that neither could for 
one moment, either in form or habit, be mistaken for any de- 
scribed Euglypha or for Trinema. But besides the smooth 
exterior, our forms are distinguished from those genera by 
the flexible infolded frontal region of the “ test,” so unlike 
the rigid neck-like aperture of theirs, as the case may be, 
either prolonged externally or introverted. 
