40 THE ROTIFERA. 



F. MICEOPUS, Gosse, sp. nov. 

 (PI. XIX. fig. 12.) 



[SP. CH. Foot inconspicuous ; toes minute, conical. No eye visible. 



This small species, known only by a single example, is much like F. forficula in 

 form, but the toes are very small in proportion, being cones whose length little exceeds 

 the breadth of their base. The animal is clear and colourless ; very soft and flexible ; 

 constantly contracting and lengthening. The anterior parts are somewhat thick, 

 gradually attenuating to the foot, where the width, both transverse and vertical, is less 

 than half that of the head. An occasional glimpse of the side (fig. 12a) showed that the 

 face was truncate, and obliquely prone ; whereas the front viewed dorsally was obtusely 

 conical in outline. But the extreme changeability of form, especially in the fore parts, 

 and the flexibility, were notable. No brain could be defined, nor any trace of an eye. 

 Though, according to Ehrenberg's arrangement, this should be a Pleurotrocha, if the 

 eye is really wanting, yet the whole habit and form of this creature showed its affinities 

 to be with Furcularia. I found the specimen described in water sent me by Mr. Bolton 

 in December 1884, obtained from a boggy ditch in Sutton Park. P.H.G.] 



Length, ^ inch. Habitat. A ditch near Birmingham (P.H.G.). 



F. LONGISETA, Ehrenberg. 



(PI. XVIII. fig. 16.) 

 Notommata longiseta . . . Ehrenberg, Die Infus. 1838, p. 432, Taf. liii. fig. 2. 



[SP. CH. Body cylindric, round at each end ; foot thick, one-jointed ; toes twice as 

 long as the body, unequal. 



The cylindric body is slightly arched, but retains an uniform thickness. The whole 

 rounded front is ciliate, with a semi-prone face. The toes, jointed on a thick cylindric 

 foot, seem made of spun glass, thick at the base, but tapering to great tenuity, though 

 not very acute. The right is about one-fourth longer than the left. The mastax and 

 its trophi, in situ, closely resemble those of Furcularia gracilis ; but I have not resolved 

 them satisfactorily. A great brain carries an opaque terminal mass at its point. The 

 front, viewed dorsally, has the outline of a low cone, with a single minute red eye at the 

 very point ; and now and then I have seen pushed out what seemed minute lateral 

 auricles ; yet with no perceptible acceleration of motion. The contractile vesicle is 

 very large. There is a prominent angle on the occiput, which may indicate a protrusile 

 antenna ; but I have not seen it exserted. 



I had this pleasing species in 1851, from a dyke near Stratford, and presently after- 

 ward from Maidenhead. Recently it has occurred in water from Snaresbrook sent me 

 by Mr. H. Davis, and from Woolston, by Miss Davies. It swims slowly, often turning 

 to one side ; occasionally throwing apart the long toes, and springing when alarmed, 

 so as to fling the body more than its own length in an uncertain direction, the sound made 

 by the toes striking the glass on such occasions being distinctly audible. P.H.G.] 



Length, to tips of toes, 7 ! ff to yi^ inch. Habitat. Pools in the southern half of 

 England (P.H.G.). 



F. .EQUALIS, Ehrenberq. 

 (PI. XVIII. fig. 15.) 



Kotvi>i.niata ecqiuilts . . . Ehrenberg, Die Infus. 1838, p. 432, Taf. liii. fig. 3. 



[SP. CII. Indistinguishable from the preceding, save that the toes are equal. 

 Though the resemblance between these two species is very close, Ehrenborg was 



