26 THE EOTIFEEA. 



a rather thick ribbon, slack, but scarcely convolute, passes down each side, apparently 

 lost in (perhaps beneath) the lateral brain-sac, bearing sundry vibratile tags, and merging 

 into a small contractile vesicle. The alimentary canal and the ovary were both amply 

 sacculate in such specimens as I have examined. 



I first met with this fine species on the dichotomous leaves of the Water Crowfoot, 

 growing in a sunken pan in my own garden near London, in the summer of 1849. It 

 was vigorous and active, swimming rapidly through the water, with a headlong, pushing 

 violence, or fixing itself slightly by its toes, and thrusting about its head in all directions. 

 It seemed fierce and voracious ; for, though I did not actually see it swallow food, it 

 several times munched with apparent greediness the side of a large Rotifer, returning 

 to the attack, and seeming to bite ferociously. The Rotifer, if not materially injured, 

 was thoroughly alarmed. I have since met with the species, but very rarely. P.H.G.] 



Length, ^ inch. Habitat. Near London (P.H.G.) ; Sandhurst, Berks (Dr. Collins). 



N. TUBA, Ehrenberg. 



(PI. XVII. fig. 8.) 

 Notommata tuba .... Ehrenberg, Die In/us. 1838, p. 433, Taf. xlix. fig. 3. 



[SP. CH. Body trumpet-shaped; brain clear; a cervical eye ; toes furcate, conical, 

 minute. 



My right to mention this species rests on a pencil-sketch which I made from life, 

 many years ago, and which I still possess, but without sufficient detail to warrant de- 

 scription, and of which I have preserved no accompanying notes. In Dr. Collins's Note- 

 book, which is kindly entrusted to me, there is a pencil-drawing to which he has 

 attached this name ; but this also is unaccompanied by any note, except the date 1866. 



From Ehrenberg's figs. I conjecture that its affinities are with Hydatina, the 

 cervical eye notwithstanding. P.H.G.] 



N. LACINULATA, Ehrcnber<j . 



(PL XVII. fig. 9.) 

 Notommata lacinulata . . . Ehrenberg, Die In/us, p. 428, Taf. li. fig. 4. 



[SP. CH. Small; body cylindrical, thick, broadly truncate; brain clear; foot 

 short; toes long; trophi forcipate; incus much developed, hemispheric; mallei very 

 small. 



This tiny, sprightly atom is of pleasing form ; vertically viewed, it is a very regular 

 oval in outline, the head dilated, archedly truncate, and of a width, when the hemi- 

 spheric auricles are out, equal to that of the body ; while at the other end the acute 

 divergent toes, set on a very short foot, make an elegant finish to the form. Laterally 

 viewed, the diameter is nearly the same, the fore and hind extremities nearly perpen- 

 dicular and nearly equal, the dorsal line arched, the ventral straight, the foot and toes 

 set-on at the end of the latter. 



The mastax is very large and the trophi peculiar. The incus is remarkably developed, 

 the fulcrum stout and long, the rami forming, when closed, a transparent hemisphere, 

 " so as to resemble, when viewed obliquely from above, a globe of glass standing on a 

 pedestal." (See my mem. " On Manduc. Org." in " Phil. Trans." 1855, p. 432, pi. xvii. 

 figs. 32-34.) The tips of the rami are habitually projected in greater or less degree 

 from the front, so that there is no buccal funnel proper. Behind the mastax there is 

 a large dilated pale-red eye, seated near the middle of a moderate brain, which carries 

 no opaque chalk-granules. 1 The alimentary canal is ample, usually filled with food of a 

 rich yellow-brown hue, which adds much to the attractiveness of the animal. 



1 Eckstein finds his usual two red specks at the ciliate front, in addition to the large red eye at 

 the bottom of the brain ; but he does not associate them here with tentacular seta. 



