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such a degree that the skin at this place appears quite white, 
whilst in its ordinary condition, as above mentioned, it is of 
a yellow tint. Sometimes (says the author) I saw pale, long, 
hyaline processes from the interior press against the outer 
capsule, but I was unable to establish with certainty whether 
the latter became broken through in the previously described 
manner thereby. It appears, however, undoubted and even 
essential, that this problematic ‘ skin’ must, in fact, possess 
such an extensibility and elasticity, that it becomes ulti- 
mately broken through by bodies pressing against it, be it from 
without inwards by inception of food, or be it by projected 
pseudopodia. But just as undoubted and essential is it also, 
that subsequently, as well following the incepted food-parti- 
cles, as after the pseudopodia are again retracted, the breaches 
which had taken place should become at once again restored, 
through the elasticity and easy fusibility of the skin. 
“‘I was not able to find a nucleus in the interior of the 
granular parenchyme, but, however, some minute contractile 
vesicles ; its dimensions reach a diameter of 0°04 mm.” 
This, then, is all Greeff gives us in connexion with these 
interesting forms. It is a pity his account of the two latter 
forms is so short, but should they turn up in other quarters, 
his figures would most likely render the identification not 
difficult. It is perhaps also, to a certain extent, a pity, that 
he calls the outer coat by such varied names as “ Saum— 
Schale—Haut—Kapsel, &c.,” when, perhaps, the more general 
term “ Hiille,” might, at least, be preferable, that part of the 
structure being, at all events, one and the same thing through- 
out. Combining, however, what we have learned respecting my 
own new form, brought forward on the present occasion, with 
what Greeff has communicated, of the three he has named, 
we gain a conception of a seemingly distinct generic type of 
rhizopod, previously to his memoir, not defined, and one of 
considerable interest. 
It may look somewhat like temerity, on my part, to essay 
to do what Greeff has unfortunately left in abeyance ; that is 
to try to comprehend in a diagnostic form what appear to be 
the characteristics or essentials of this genus, so far as obser- 
vation reaches. 
Genus, Amphizonella (Greeff ). 
Generic characters —Rhizopod, with a “nucleated” body- 
mass, enclosed in a distinct (and separable), more or less 
pellucid, elastic and yielding investment, through which it 
