54 THE ROTIFERA. 



protrusilc ; alimentary canal vcrij large, itrojectcd behind and above the masiax, always 

 filled icilh green matter. 



This is an animal of no inconsiderable size, which lias the technical characters of 

 Diglena, but has little alKnity with that genus, in structure or manners. My first ac- 

 quaintance with it was in October 1849. A filamentous plant, growing in a pan sunk in 

 my own garden, was thickly covered with a floceose matter, inhabited by numbers of 

 Stentor polnmorphus. Among them were specimens of this Diglena (?). In January 

 1851, I again found it in the same water, and on a subsequent occasion; but I have 

 never mot with it since. 



The form is gracefully swelling and vase-like, not at all resembling a Diglena in 

 appearance ; it has much the aspect of being loricate, but it is not. Two eyes are placed 

 at the extreme front ; small, so close together as to be readily mistaken for one, brilliantly 

 crimson. The transparent mastax, in situ, shows a pair of incurved strong pincers, 

 whose approaching tips are two-toothed. These can be extended from the front for 

 half their length, and seem to be a formidable instrument for seizing prey. These are, 

 no doubt, the rami of an incus. What appears remarkable is that a great saccular lobe 

 of the stomach runs up behind the mastax into the occiput, and divides into two lobules. 

 The whole alimentary canal, with these lobes, was, in every example, uniformly filled 

 with round green granules, the exact similarity of which to the component granules of 

 the Stcntors and the Loxodes, which abounded in the same water (together with various 

 species oi Englena), suggested that the normal food of the Rotiferon may consist of the 

 juices of these Polygastrica, especially as its formidable forceps seems to indicate car- 

 nivorous propensities. The long straight rod-like toes are now and then turned up, so 

 as to incline over the back ; occasionally their tips are crossed. — P.H.G.] 



Length, y,',^ inch. Habitat. A garden-pan near London (P.H.G.) : rare. 



Genus DISTEMMA, Ehrcnherg. 



[GEN. CH. Body more or less cylindric, long, slender before, su-ollen behind, ver- 

 satile ; tico cervical eyes; front furnished tvith a fleshy proboscis; toes two, furcate. 



This somewhat obscure genus Ehrenberg constitutes on four species. These, how- 

 ever, must be reduced to two : for D. setigerum clearly belongs to the family Eattulidce ; 

 and D. marinum is one of the Loricata. The others I have not met with. But I 

 enumerate three species, apparently undescribed, which seem to come into the genus. 



In aspect and manners they closely resemble Diglena, especially in their long, lithe, 

 versatile forms, generally swollen behind ; in the presence of soft tentacular appendages 

 to the front ; in the forcipate form and protrusile character of their trophi ; and in their 

 fierce raptorial habits. The species inliabit the sea and fresh waters. — P.H.G.] 



D. RAPTOK, Gosse, sp. nov. 

 (PI. XIX. fig. 1.) 



[SP. CH. Body long, gibbous behind, very changeable ; front tvith a long projectile 

 lip ; foot short ; toes small, slender, decurved. Marine. 



The lithe flexible form is usually lengthened, slender in the middle, becoming high 

 behind, its outline descending in an abrupt curve to the very small foot. This is armed 

 with two toes, whose tliickness tapers abruptly at the middle (fig. Ic). It is near 

 D.forcijjatum, but is distinguished by this peculiarity of the toes, and by their curvature. 

 And it is marine. The head is rounded, the front produced into three fleshy ciliate 

 points, and a conical projection on each side. The central point is probably the tip of a 

 curious fleshy process, wliich is now and tlieu rapidly pushed out and in (figs. 1, la), quite 

 straight, thus dift'ering from tlie proboscis of Diglena. The lateral projections, when this 



