102 THE EOTIFEKA. 



near together about the middle of the back, and the fourth has also two at the bottom 

 of a strong constriction where the body begins to be attenuated : this pair appears to ter- 

 minate the body (fig. 5b) when contracted, the posterior segment being bent up and 

 forward. The upright spines shown in Ehrenberg's figure I have represented in fig. 5b. 

 They are situated one on each side, level with the second pair of dorsal spines. Under 

 pressure, and when seen dorsally, the body assumed the appearance of fig. 5d ; by 

 which the relative positions of the spines is better shown. The frontal column is large 

 and cylindrical, resembling that of R. macrurus ; the tip, which is truncate, but fur- 

 nished with a little protrusile proboscis, is ciliated, and capable of a rotating vibration. 

 The wheels are large, and the sulcus at the chin is deep. 



The antenna is large and prominent ; it is capable of being erected, of projecting 

 horizontally, or of hanging downward. It consists of two joints, the first tapering to 

 the articulation, which is telescopic, the second dilating to the tip, which is distinctly 

 three-lobed. The deep yellowish umber hue of the body, and its close-set longitudinal 

 furrows, effectually impede the discernment of the internal organs ; but I could see that 

 there is a capacious digestive canal, which attenuates near the fourth row of spines, and 

 terminates in a cloaca at the end of the next segment. Near this point is a small con- 

 tractile vesicle. A large oval transparent ovum was seen in the ventral region of the 

 trunk. As it showed the jaws perfectly developed, I presume the species to be vivi- 

 parous. This species very seldom expands its corona while stationary ; it is impatient, 

 restless, perpetually crawling, or pushing about its closed fore-parts in all directions, 

 while attached by the foot. Generally the expansion of the corona is instantly followed 

 by the detachment of the foot, and away the creature shoots head-foremost, and glides 

 rapidly about the live-box until it is suddenly arrested by coming into contact with some 

 object. P.H.G.] 



Length. When extended, about 3 V mcn - Habitat. Ponds near North London, 

 (P.H.G.): rare. 



P. TUBERCULATA, Gosse, sp. nov. 



[SP. CH. Scarcely distinguisliable from P. aculeata, but the surf ace beset with rough 

 tubercles, instead of spines. Body much fluted longitudinally ; antenna with a small 

 three-lobed, club-shaped, terminal joint ; eyes very small; teeth three, thick; spurs 

 long, slender, slighly sigmoid, acute. Dark brown. 



A species in most particulars resembling P. aculeata, with like club-shaped antenna, 

 much corrugated and plicated, and of a pronounced wood-brown hue, but having the 

 recurved spines replaced by rough irregular tubercles, has occurred in water sent by 

 Mr. Bolton, Birmingham, from Button Park. The sediment of this water, of rich golden 

 brown hue, largely consisting of floccose faecal deposits, as I suppose, full of great 

 Desmids and other algse, has proved usually rich in Rotifera. Among them, grubbing 

 sluggishly, was this uncouth Philodina ; the whole body clogged with sediment. For 

 some time I supposed that it might be P. aculeata, the spines modified into tubercles ; 

 but I have found P. aculeata repeatedly since, with the spines clear and sharp, exactly 

 as I had drawn them from life thirty-five years ago. And I have also since found 

 numerous examples of this tubercled form, from other waters, in no respect differing 

 from the first ; so that I have no doubt of its being an undescribed species. It has 

 very close resemblance to Rotifer tardus, except that the two eyes are not in the frontal 

 column, but on the level of the mastax. It has also the manners of that species, sloth- 

 ful, wallowing in the gelatinous floccose, reluctant to move, but ready to rotate. 



The frontal column, when extruded to the utmost, is tipped with vibratile cilia, 

 amidst which a minute proboscis projects, which is double, consisting of two obtuse 

 blade-like clear Iamina3, side by side, and slightly divergent. 



Length, ^ inch. Habitat. Button Park, Birmingham (P.H.G.) : rare. P.H.G.] 



