HYDATINAD^; NOTOMMATAD.E. 19 



tho gastric glands are pear- shaped. But gastric glands often differ in shape, and so 

 occasionally does the number of teeth in an uncus. At the most, chilensis may be a 

 variety ; it is -^ inch long, and was found in St. Jago, Chili. 



H. TETKAODON, and H. MACKOGNATHA, Schmarda (135). See note 1, Sup 1 , p. 8. 



Genus TRIPHYLUS, Hudson. 



GEN. CH. A genus of the NOTOMMATAD.E ; body sub -cylindrical, somewhat com- 

 pressed, gibbous dor sally ; foot short, retractile, on the ventral surface; eyes two, frontal. 



TEIPHYLUS LACUSTEIS, Ehrenberg (PI, XXXII, fig. 16). 

 Diglena lacustris ..... Ehrenberg (42). 



SP. CH. Corona without setigerous prominences ; ciliary wreath single ; foot 

 about one-fifth of the total length ; trophi forcipate ; skin slightly thickened into two 

 ridges on the dorsal surface. 



No one appears to have studied this Eotiferon since Ehrenberg described it ; so it was 

 with great pleasure that I examined some living specimens, kindly sent to me by Mr. 

 George Western, who had found them in a pond at Littleton. 



The animal closely resembles Notops clavulatus in the greater part of its internal 

 structure, and Notops hyptopus in its general shape ; while it differs from both in having 

 two frontal eyes, and no solitary cervical one. It is quite unlike the Diglena ; among 

 which it was placed solely on account of its two frontal eyes. The body is sac-like ; not 

 nearly so compressed as that of hyptopus ; the head, transversely truncate and slightly 

 convex ; the corona, a simple marginal wreath, notched ventrally ; the foot small, ven- 

 trally placed, retractile, and with two small toes. The mastax (fig. 16 b) is globular, with 

 a backward projecting part, like a stalk, containing the fulcrum. The trophi are of a 

 forcipate pattern, and can be best understood from the above figure. The oesophagus 

 is very long, thin, and expansible, exactly like that of hyptopus or clavulatus : the 

 stomach is long, conical, sacculated, studded with globules, and with three ribbon-like 

 coecal projections on each side. The gastric glands are long cylindrical organs, bifurcate 

 at their free ends. There is a good-sized contractile vesicle ; and the lateral canals and 

 vibratile tags are obvious. The nervous ganglion is small, lying between the eyes and 

 the dorsal antenna ; which latter is a mere setigerous pimple on the neck, with two 

 threads passing to it from the nervous ganglion. Very powerful muscles pass from the 

 head down the whole length of the body- cavity and are fastened at its base ; thus com- 

 pleting a picture which might almost stand for that of Notops clavulatus itself. 



Of course lacustris is not technically a Notops ; its two frontal eyes appear to forbid 

 its entrance into that genus, just as they seem to invite it into the genus Diglena. For 

 all that, its true affinities are with hyptopus and clavulatus, for it is internally like the 

 one, and externally like the other. 



Length, -^ inch. Habitat. Littleton, near London (Western). 



CorEus EHRENBERGII, Ehrenberg (PI. XXXII. fig. 17). 

 Notommata copeus Ehrenberg (42). 



SP. CH. Front furnished with a pair of long thick cylindrical auricles, ciliated at the 

 tips, projectile and retractile ; lumbar regions with a stout seta on each side, projecting 

 at right angles to the lateral surface; tail pointed, stiff; chin projecting moderately, 

 ciliated ; brain threefold. 



This fine Kotiferon is so like C. labiatus, when its auricles are withdrawn, that it 

 might easily be mistaken for that animal. It differs from labiatas in the shape of the 

 front ; in the possession of large telegraph-like auricles ; in the much smaller size of 

 its ciliated lip ; and in its foot having three joints instead of two. Moreover, T\Ir. Gosse, 

 although he met with several specimens of labiatus, never found one with the gelatinous 



