THE LOWEST FORMS OF LIFE. 151 
“ So, these little floccalent particles that float about in the 
water are portions of the indigo in solution, are they ?” 
“ Tes ; they are the magnified flakes of that substance held 
suspended in the water ; and now if you look at the rim of the 
calyx of one of the Yorticellae, you will find that the current 
brings a continuous supply of the indigo into the mouth or 
oral aperture, as it is termed, of the Vorticellse.” 
“ So it does,” said my young pupil, after watching the 
operation for a time ; “ and inside of the cup little blue balls 
or globules are formed, — portions of the food undergoing 
digestion, I suppose?” 
“ See how acute your faculties are becoming by observation,” 
I exclaimed. “ The globules are, indeed, portions of the food 
undergoing digestion, and I will describe this process, so far 
as we are acquainted with it, in Vorticella and other infusorial 
animalculse. 
“ The body or calyx of the animalcule is composed of a 
little mass of substance similar to that of Amoeba, but 
Vorticella is inclosed in an elastic contractile skin or in- 
tegument. Some observers believe this f skin ’ to be made 
up of two distinct membranes, the inner one being contrac- 
tile, and extending into the pedicle or foot-stallc, so as to 
constitute that remarkable contractile filament, ivhich imparts 
the power of coiling and uncoiling to the appendage in ques- 
tion. (Plate viii., fig. 3 b.) The soft semi-fluid substance 
of the calyx contains a rudimentary, digestive, and cir- 
crdating apparatus, the food being admitted through an 
aperture situated within the rim of the cup 
I have been trying to call to memory some familiar object 
that will afford you an idea of the calyx or cup of V orticella, 
but the only one to which I can compare it is a common 
breakfast cup into which a circular piece of cardboard has 
been inserted, so as to leave only the rim of the cup visible. 
Suppose you were to cut a piece of paper or cardboard to 
the shape of the cup at its widest part, and make a hole in 
the cardboard a little to one side from the centre, you woifid 
imitate to some extent the <r disk/ as it is called, which closes 
the wide aperture of the calyx of V orticella. The circlet of 
cilia is disposed spirally upon the disk within the lip or rim, 
and is continued a little way into the mouth or oral aperture, 
which is represented in my simile by the hole in the card- 
board that closes the aperture of the cup (fig. 3). 
“Now, watch the current of indigo carefully, and you will 
perceive that it forms a kind of vortex, or whirlpool (hence the 
name Vorticella), the object of which is, that any particles of 
matter unsuitable for nutriment may be rejected; and, 
according to the obsei'vations of some microscopists, there is 
NO. II. M 
