NOTQMMATADjE. 5 



rant me in placing it in this genus. Indeed, when, five-arid- thirty years ago, I first met 

 with it, I concluded that it was identical with Ehrenberg's N. centrum. But I have 

 lately seen several more examples, which have convinced me that it is still an un- 

 described species. 



The form is rudely cylindrical, with many irregular constrictions, and the abdominal 

 regions somewhat swollen. The front is rondo-truncate, with a minute auricle on each 

 side. These seem scarcely protrusile, though the oval space in which ciliary action is 

 seen appears in each. The ciliated face is prone, and reaches far down ; no lip appears. 

 At the hinder extremity there is a distinct tail, small, saccate, almost amorphous, 

 beneath which the cloaca opens, as I saw by the actual emptying of the rectum. A 

 very short foot carries two minute, conical, pointed toes. The brain consists of three 

 sacs, of which the central hangs low, being seen behind the rnastax, and as usual forms 

 a long tube at the origin, in which is the eye of lenticular form, and brilliant crimson 

 hue. The lateral sacs are moderately short. All three are more or less occupied with 

 opaque granular matter ; but in the central sac this is generally (not always) so much 

 diluted as to be pellucid. The central sac, too, is occasionally seen truncate at its lower 

 end, exhibiting very distinctly at its margin the separate cells of which it is composed. 

 The trophi are normal : the mallei apparently four-fingered. The alimentary canal is 

 large, saccate, furnished above with small globose gastric glands, and not sensibly 

 divided ; its central longitudinal cavity may usually be traced, full of digesting food of a 

 dark umber-hue, while the thick surrounding walls are tinged with the same. The vo- 

 luminous ovary, forming a wide horseshoe across the ventral region, its horns directed 

 backwards, is full of clear embryonic vesicles, and often carries a dark maturing egg 

 which I have seen discharged. The branchial system has the usual form of a rather 

 thick cord (probably tubular), not twisted, but hanging so loose as to be thrown into 

 many curves, with at least three vibratile tags on each, and the usual contractile vesicle 

 of moderate size occupying the hind mid- ventral region. Muscles, both longitudinal and 

 transverse, agree with those that I long ago demonstrated in Not. aurita. 1 The whole 

 head is usually tinted with buff, and the mastax-front with red-brown. 



My first example of this species was found in June 1850, in a phial dipped on Hamp- 

 stead Heath three weeks before. The more recent were in the sediment of a phial sent 

 me by the kindness of Dr. Collins, from the historic pool in Sandhurst Wood. The 

 creature, like its congeners, is slow and deliberate in manners, burrowing and rooting 

 in its floccose surroundings. Its motions are much like those of the water-bears ; in- 

 deed, on first catching a glimpse of my subject among the half-hiding sediment, I have 

 repeatedly been doubtful whether I was looking at a Tardigrade or one of these massive 

 NotommatadcB, P.H.G.] 



A specimen of Mr. Gosse's Copeus Cerberus, which I found in some water from 

 Button Park, Birmingham, enabled me on one occasion to obtain an excellent view of 

 the mastax and trophi ; for it every now and then slowly turned its head back, so as to 

 bring its ciliated face up to the cover-glass, and thus to rotate the mastax, for me, with 

 all its parts in their natural position. I could distinctly see the massive malleate trophi 

 unusually thick and broad ; the short, wide, yet graduated teeth of each uncus opposing 

 each other at the top of the mastax, like the fingers of the two hands brought just to touch 

 at their tips. Immediately above them were two very prominent lips, like a parrot's 

 beak, and evidently of a much harder substance than the rest of the mastax : they were 

 seated upon it, on each side of the opening between the buccal funnel and the teeth. 

 These J saw repeatedly open and shut as food passed down the funnel to the trophi. 



Length, ^y inch. Habitat. Hampstead Heath ; Sandhurst, Berks (P.H.G.). 



1 Trans. Micr. Rnc. T,cmd. vol. iii. p. 101. pi. xv. 



