24 Mr. H. J. Carter on Freshwater Rhizopoda 
in process of digestion. Thus there are no chlorophyll-cells as 
in D. pyriformis, but small brown cells, yellow oil-globules, and 
reproductive cells, all of which do not appear in the latter, un- 
less, as above stated, I have mistaken the “‘ reproductive cells” 
in D. pyriformis for large starch-granules, which the sequel will, 
I think, make probable. Let us now review these parts more in 
detail. 
1. Small brown cells (PI. I. fig. 64). These are globular in 
form, filled with granular protoplasm, and about 5,),,th of an 
inch in diameter, not near so numerous or so striking as the 
chlorophyll-cells. in D. pyriformis, although they, with the 
yellow oil-globules, appear to give the light brown colour to the 
species. 
2. Oil-globules (c). These are more striking than in D. py- 
riformis, from their constant presence, greater number, and 
bright amber-colour: they vary in size, and, under the appli- 
cation of a solution of iodine in iodide of potassium, lose their 
yellow colour, but only to become more brilliant and refractive. 
8. Starch-granules (d) and nucleus (fig. 6). The same as in 
the green specimens of D. pyriformis, where the latter has be- 
come spheruliferous. The nucleus is also about the same size, 
(the =4+st part of an inch in diameter), but the spherules more 
marked and sometimes granuliferous. As the nucleus in all the 
specimens which I examined, and which were very numerous, 
was in the same condition, while in its original state it probably 
bore the usual appearance, viz. a circular discoid body (the 
nucleolus) attached to the inner surface of a larger translucent 
and spherical cell (the nucleus), it may be that this is the state 
in spring, and the former the autumnal one, indicative of the 
time of the year at which the animal generates. . 
4. Reproductive cells (e, f). These are certain cells of an 
oval or circular shape, filled with homogeneous contents, colour- 
less, more or less refractive, and generally about ~},th of an inch 
in diameter, but varying to twice this size or more, even in the 
same animal. They also vary in number, from ten to twenty or 
more, and have been seen frequently both with and without the 
presence of the nucleus in its spheruliferous condition. On the 
application of iodine, they, for the most part, assume a light 
amber colour, and sometimes present granuliferous contents (/), 
which distinguishes them at once from the starch-granule; but 
they also present occasionally a claret-colour, although never so 
deep or with such homogeneous contents as the starch-granule. 
As before stated, I suspect that these cells also exist in D. pyrt- 
formis, and that I have mistaken them there for large starch- 
granules. 
In no instance have I yet found the body of D. compressa 
