20 THE EOTIFEEA. 



brown granular food. The toes are usually held close appressed when the animal 

 is gliding ; but often expanded. It was lost before I could complete my observation. 



This individual was found in Monk Mire Loch near Dundee, in August 1885, 

 among slender filamentous weed crowded with minute diatoms, making dense masses 

 of impalpable floccose. The former was from Woolston Pond, Hants. P.H.G.] 



Length, T ^ ? inch (?). Habitat. Woolston ; Birmingham ; Dundee (P.H.G.). 



P. LEPTUKA (?), Ehrenberg. 

 (PL XVIII. fig. 4.) 



[SP. CH. Toes moderately long, slender, acute, slightly decurved ; face oblique. 



This species is of equal rarity, in my experience, with its two congeners ; a single 

 solitary example alone having occurred to me, and that at about the same time. 



The ciliated front is much more prone than I observed in the others, and the mastax 

 was at one time so thrust forward that the trophi were brought to the very face, as we 

 see with many of the Notommatce. The outline is gracefully swelling, and tapering be- 

 hind; and the form and curve of the slender toes are elegant. P.H.G.] 



Length. About T J inch. Habitat. Woolston Pond (P.H.G.). 



P. GIBBA (?), Ehrenberg. 

 (PI. XVIII. fig. 5.) 



[SP. CH. Short and thick in proportion to its length ; toes moderately long and 

 broad, nearly straight. 



It is with great hesitation that I attach Ehrenberg's name of gibba to this little 

 species. The general shortness and stoutness of form agree, and, though the lumbar 

 parts of the body want the plumpness whence he has selected an appellation, this 

 may be a variable character dependent on repletion of the alimentary canal. My figure 

 was drawn from life ; but the example was lost before I had completed my observations. 

 It was in the early spring of 1885 ; but I made no record of the source whence it was 

 obtained. P.H.G.] 



Length. About 3 .^ 5 inch : whereas Ehrenberg gives ^\ G inch as the average of his. 



Genus NOTOMMATA, Gosse (nee Ehr.). 



[GEN. CH. Body not annulose, cylindrical, furnished behind with a projecting 

 tail ; special organs (auricles) on the head for locomotion, evertile and protrusile ; 

 brain large., containing opaque chalk-masses; trophi virgate. There are species in 

 which one or more of these characters may not be found. 



The genus Notommata of Ehrenberg, even as it left his pen, was a heterogenous 

 mass of dissimilar species. Many naturalists have indicated the need of dividing and 

 redistributing the unwieldy group ; but none have yet ventured upon the task. I propose 

 to break it up into three distinct genera. The family Asplanchnada having been already 

 formed, some species of large size, sacciform body, and hyaline transparency, migrate 

 thither ; while others of similar appearance may be associated with the Hydatinadfe. 

 These being eliminated, there comes the curious species N. copeus, which Ehrenberg 

 distinguished by large dimensions, a fusiform body, a distinct tail, and organs of special 

 sense, projecting from the lumbar regions, as well as from the head. As a number 

 of others, allied to this form, have been discovered, I form them into a separate group 

 with the generic appellation of Copeus. Then there is a groiip of conspicuous species, 

 marked by auricles, by a more or less distinct tail, and by the brain being unusually 



