60 THE ROTIFERA. 
glass as to resist the foree with which the surrounding water is carried up into a pipette 
by the pressure of the atmosphere. It is doubtless by the adhesive power of the clear 
glue secreted and poured out by the oblong foot-glands. In Mastigocerca this may often 
be seen running down the outside of the toe, its production seemingly subject to the 
animal's will. When first put into the live-box, it is commonly poured forth abundantly, 
so as to accumulate around the point, and to drag in a thick glairy stream behind it. 
I have seen it surround the terminal half of the spine to a thickness four times as great 
as that of the spine itself. Or it will run from the base downward, like a thick spiral 
cord. Sometimes it is not perceptible. The male has not been detected in the family. 
—P.H.G.] 
M. carinata, Hhrenberg. 
(PIE 75) 
Mastigocerca carinata . . Ehrenberg, Die Infus. 1838, p. 460, Taf. lvii. fig. 7. 
[SP. CH. Body long-oval ; lorica ridged ; ridge high, arched, reaching to middle 
of body ; toe straight, equal in length to body-and-head ; sub-styles very minute. 
The height of the dorsal ridge is very characteristic in this familiar species, rising, 
in the midst of its length, to fully half of the vertical thickness (7.e. from back to breast) 
of the body. Its cessation, too, just beyond the middle of the back, gives a peculiar 
humped outline to the forepart, viewed laterally. The belly-line is about equally curved 
with that of the back. The ridge, as already observed, is not set-on straight down the 
dorsal centre, but on a line that slants considerably to the left, while in its elevation it 
leans over to the right. It is manifestly hollow along its base, for the viscera may often 
be seen extending into it for a little way. It is marked on its basal part, through its 
length, with close-set corrugations. The front is rounded, with many minute eminences, 
on which the cilia, which make two distinct vortices, are set; they increase in size 
and height to the occiput, where an antenna projects, capable of being erected or inclined. 
A long occipital brain carries a rather large bright-red eye, set like a wart at its interior 
lower angle. The mastax, a pear-shaped bag, is enormous, reaching, from the front, 
half the body-length. It contains an incus with a slender straight fulerum, the rami of 
which are obsolescent and the alule very large, and two bent mallei, unequal in size 
and form. There is a very small contractile vesicle, whose period is shorter than I 
have observed in any other Rotiferon, twenty-five times a minute. The distension of 
the viscera conceals the branchial vessels, but I have seen one vibratile tag. 
The foot consists of an ovate bulb, to which is jointed the toe as a slender spine in the 
midst of two or three bract-like accessory styles, one of which is slightly longer than the 
others, distinctly moveable. The toe moves in all directions except backwards.—P.H.G.] 
Length. Of lorica, 1, inch; of toe, ;}, inch; depth to summit of ridge, 54, inch, 
Habitat. Pools; generally distributed: common. 
M. LOPHOESSA, Gosse, sp. nov. 
(Pl. XX. fig. 10.) 
[SP. CH. Body long-oval; dorsal ridge reaching to the foot, nearly uniform in 
height ; toe straight, two-thirds as long as body ; sub-styles one-third of toe-length. 
This I think a well-defined species. The ridge attains nearly to as great a height as 
in carinata, and is continued to the base of the foot. Its outline runs in several arches, 
and descends rather abruptly at the end. Itis marked with faint radiating corrugations. 
The principal toe is a straight slender style, gradually tapering to a fine point, as in 
carinata, but not quite so long in proportion ; and the accessory styles, of which I could 
discern two, are of unequal length, the longer equalling fully one-third of the principal ; 
whereas in carinata it is not more than about one-eighth, by very careful micrometrie 
measurement, The mastax and jaws seemed much shorter than usual, but of the common 
