Twenty-four more New Species of Rotifer a. By P. H. Gosse. 8(39 



It suggests the odd notion of a creature carrying its great clumsy head in 

 a bandbox. (Fig. 18.) 



19. Monura Bartonia. Lorica ovate, moderately compressed, dorsal 

 outline (viewed laterally) one-third of a circle, ending in triangular 

 points, which have the dorsal side slightly excavate : one eye frontal : toe 

 straight, slender, acute, more than half as long as the lorica, shouldered 

 dorsally. Length, from frontal hook to tip of toe, 1/173 in. Lacustrine. 



The genera Golurus and Monura (if, indeed, they are not one) appear 

 to contain a large number of species, peculiarly difficult to define satis- 

 factorily. Yet this and the following are, I think, to be distinguished. 

 The toe and foot together are nearly equal in length to the lorica. I 

 could find no trace of a median line in the toe. Its extreme length and 

 tenuity are notable. Each posterior point of the lorica forms an equi- 

 lateral triangle, clearly defined from the general area of the lorica, by a 

 line — the base of the triangle. These two triangular termini are of ex- 

 cessive delicacy, and may easily escape a cursory notice. On the extreme 

 front, under the frontal hook, is a small dark crimson eye, Uke a wart on 

 the face. 



Its manners are those of so many of its fellows, remaining long 

 totally withdrawn between the closed lorica-plates in front, pivoting and 

 swaying on the toe-tip incessantly for hours. I first obtained it, in 

 the spring of this year, from a pond known as the Reservoir, at Barton, near 

 Torquay. Since then I have met with single specimens from many 

 localities, and in abundance in the Kingskerswell mill-stream. (Fig. 19.) 



20. Monura lonclieres. Dorsal outline narrowly ovate, lateral nearly 

 semicircular ; lorica rounded behind, with a median angular notch : toe 

 shouldered dorsally, excessively long and slender. Total length 1/200 in. ; 

 vertical depth 1/550 in. Marine. 



The most striking points in this beautiful species are its great depth 

 (from back to belly), making about a half-circle, and the tenuity of 

 the toe, which seems indivisible. This runs to so exceedingly fine a point 

 as to escape notice, except with the most delicate focusing ; even with a 

 quarter objective, and the best possible hght. The foot, of two condyli- 

 form joints, and the toe, together, are fully equal to the lorica in length ; 

 viz. 1/400 in. The ventral cleft is narrow, straight-sided, shghtly 

 approximate in front, and reaching round to the occiput, posteriorly to a 

 short acute sinus (b), whose sides form a right angle. There is a brilliant 

 ruby eye about the middle of a saccate brain, and therefore cervical. 



I have examined a number of examples, at difi'erent times, in sea-water 

 obtained by Mr. Hood from the Invergowrie tidepools. In one of these 

 I timed the period of emptying the contractile vesicle to be just three 

 minutes. It had this peculiarity, that the emptying was but partial on 

 each occasion : that the bladder suddenly diminished its volume, but not 

 to a point, nor nearly. The animal's posturing manners are exactly the 

 same as described in the preceding species. (Fig. 20.) 



21. Mxjtilia looecilops. Lorica pergamentaceous, very flexible, con- 

 stantly thrown into irregular folds, whence the outline is very variable : the 

 face, in particular, is capable of great protrusion in wide plicate mem- 

 branes : prevalent figure, foot, and toes, much as in M. Teresa. Length of 

 lorica 1/240 in. ; depth 1/480 in. Marine. 



