8 THE ROTIFERA. 



tioii as the head emerges. The animal has no power of springing by means of the 

 spines, or of using them in any appreciable manner. The hind spine is similar, and 

 similarly set in a deep sulcus of the lower belly. All are dilated at their bases. 



At the very front are two minute but distinct red eyes, side by side, seated on a small 

 brain-mass, which tapers into a thread that passes to the occiput, probably to an anteima, 

 not detected. The mastax was obscure, but seemed of the Bdelloid pattern. A very 

 slender but long oesophagus leads to a vast sacculate alimentary canal, and this to a 

 cloaca at the very point of the body, behind the spine ; which hence, Herr Grenacher's 

 judgment notwithstanding, I conclude to represent the foot. A momentary action, like 

 that of a contractile vesicle, I perceived, but could not define one ; and lateral canalg 

 run down each side. Several muscles are discernible. 



The animal is vivacious, swimming freely and swiftly ; I did not see it attempt to 

 ' spring, nor to crawl ; the foot-spine was not whisked about. I first met with the species 

 in a pond in Holly Walk, Leamington, ua July 1850 ; and again lately in water from 

 Keeper's Pool, Birmingham, sent me by Mr. Bolton. — P.H.G.] 



Leng-th, yj^ to yjy inch. Habitat. Warwickshire pools : rare (P.H.G.). 



Genus PEDETES, Gosse. 



[GEN. CH. BoAy ovate, tailed ; toes absoit ; eyes tivo frontal ; two leaping styles 

 articulated to the breast. 



P. SALTATOR, Gosse, sp. nov. 



(PI. xni. fig. 10.) 



SP. CH. Leaping styles thrice the length of the body. 



This genus has a very close relation to Triarthra. It may, indeed, be described 

 as a Triarthra with the posterior style wanting. The body, though apparently soft 

 and flexible, must be considered as enveloped in a lorica, since the knobs to which the 

 styles are articulated, are hard, immoveable, and doubtless chitinous. Its form, viewed 

 dorsally, is ovate, obtusely pointed behind and broadly truncate in front. Viewed 

 laterally (fig. lOa), it is flat on the ventral, and strongly arched on the dorsal surface. 

 The dorsum rises to a marked conical elevation which is a true tail, for the cloaca opens 

 between it and the foot. The latter (or what represents it) is a small ovate terminal 

 member, within which, close to the tip, is a minute vesicle, possibly the contractile 

 bladder. The rotatory cilia are seated on a number of small projecting eminences, with 

 which the front is beset. On each side of what for convenience sake we call the breast, 

 but rather high up, is a large round shelly knob, apparently hard and immoveable. 

 Dr. Hudson (" M. M. J.") long ago explained the action of the pectoral styles in the 

 parallel case of Triarthra (see T. longiseta, p. 6). We may conclude the mechanism 

 to be the same in both cases ; but I am inclined certainly to see more than mere 

 mechanical action in these shelly knobs, viz. special muscles for the forcible and definite 

 motion of the styles, by means of a true (perhaps ball and socket) joint. Each style is 

 a highly elastic rod, thick at its origin and for a considerable distance, then gradually 

 tapering to a great attenuation, about thrice as long as the body. On the tips of these, 

 which must therefore possess remarkable firmness, the animal, now and then, suddenly 

 jerks itself away, as on a leaping-pole, with great force ; so that tliey are in an instant 

 seen stretching out at a right angle, or even more, forward. These leaping-poles are 

 composed of transparent refractive material (cliitine), resembling glass in appearance. 

 The brain has not been defined ; but two eyes, of a translucent red hue, near together, 

 are conspicuous at the very front. The mastax, far down in the body, with vigorously 

 working mallei, was visible near the middle ; and below tliis a great globose, sac-like 

 jiliinMitary canal, without visible division. The odIv specimen I have seen occurred in 



