60 THE ROTIFERA. 



glass as to resist the force 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 foofc-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. CAEINATA, Ehrenberg. 



(PL XX. fig. 7.) 

 Mastigocerca carinata . . . Ehrenberg, Die Infus. 1838, p. 4CO, Taf. Ivii. fig. 7. 



[SP. CH. Body long-oval ; lorica ridged ; ridge high, arched, reaching to middle 

 of body ; toe straight, equal in length to body -ami-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 (i.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 fulcrum, the rami of 

 which are obsolescent and the alulre 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, T J )7T inch ; of toe, T l - inch ; depth to summit of ridge, L , J - inch. 

 Habitat. Pools ; generally distributed : common. 



M. LOFHOESSA, 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-lcmjth. 



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. It is 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 micrometric 

 measurement. Thp mastax and jaws seemed much shorter than usual, but of the common 



