492 
POPULAR SCIENCE REVIEW. 
consists of many individuals (I examined one of seventy) united 
by the extremity of the foot, and radiating from a common 
centre in every direction. The heads of all point outward, and 
the ciliary currents of all give the spherical clusters a slowly- 
revolving motion as they swim. An inexperienced observer might 
for a moment suppose that he had a group of large Vorticella i 
before him, but the complexity of then* organization soon shows 
the difference between them. This species displays the exist- 
ence of muscles with remarkable distinctness, several of which 
run down longitudinally, and others go round the body trans- 
versely. The shape of each animalcule resembles that of a bell 
wine-glass when fully extended, of which the body is repre- 
sented by the vessel and the foot by the stand ; the latter, 
however, tapers to a blunt point, without any apparent division 
or expansion. The whole outline is constricted with transverse 
corrugations, and is capable, especially the foot, of forcible con- 
traction in length. The frontal disk is large, and divided 
into two semicircular portions, round which the cilia seem to be 
set; yet, when they are in active rotation, the eye cannot discern 
any break in the ciliary crown. The centre of the front rises 
into a blunt cone, on one side of which projects a little jointed 
antenna, bearing a bristle at its tip. Ehrenberg describes four 
conical papillas, all of which are sometimes bristle-tipped, but 
more commonly only the front pair. I, however, could detect 
but one.* The position of this organ, within the ciliary crown, 
is remarkable ; its ordinary place being outside, that is, below 
its plane, as seen in Melicerta. 
Two very minute eye-specks are seen, rather wide apart ; and 
below is the gizzard-like mouth containing two hemispherical 
jaws, set with teeth. The viscera are pale yellow, and the jaws 
are orange-red; else the whole animal is colourless and very 
transparent. When a cluster is taken out of the phial in which 
it is swimming about, and put into the live-box, the number of 
animals lying over each other, if it be populous, is confusing. 
The numerous feet radiating from the centre like the spokes of a 
glassy wheel, and the multitude of crystal bells around the cir- 
cumference — -each surrounded by its crown of rapidly-rotating 
and strongly marked cilia, are almost distracting. Some display 
the front, some the side ; some turn themselves so as to present 
to the eye a transverse view of the crown, others are almost ver- 
tical ; it is only in the latter, when the eye looks down upon 
the disk, that the divided structure can be seen. Some are 
continually shrinking up by forcible contractions of the foot; 
* From this discrepancy, and also from the silence of Ehrenberg respecting 
the very peculiar form of the egg (to be noticed presently), there is a possi- 
bility that mine may have been a distinct species from his. 
