88 D. BRYCE ON FIVE NEW SPECIES OF BDELLOID ROTIFERA. 



open and is not a dweller in the shelter afforded by natural or 

 contrived gatherings of dirt particles or debris like H. elegans 

 (Milne) and H. munda. I have never met with it in pools, but 

 usually in mosses (not sphagnum) growing in wet positions. 

 When the corona is displayed, it is seen to have a quite unusual 

 appearance. As in H. munda, the trochal discs are inclined 

 towards the dorsal side, but in a varying degree, and are 

 separated by a furrow deeper than in that species. The upper 

 lip rises in a broad rounded lobe which is centrally bent back, 

 leaving visible the fleshy connection, or nexus, between the short 

 pedicels. On the ventral side the under lip rises unusually high, 

 and thus in dorsal view, the collar, which passes round the 

 pedicels on either side and merges gradually into the under lip, 

 has an obliquely upward direction, not obliquely downward as 

 customary. This results in the optical presentments of the 

 rapidly beating cilia of the secondary wreath (those lining the 

 collar and passing round to the mouth), and of the cilia of the 

 principal wreath (those of the trochal discs), being to some extent 

 commingled, and there is the appearance of an annulus or ring 

 passing round the trochal discs immediately below their margins. 

 When the discs are seen so that their planes are nearly 

 coincident with the line of sight, they appear to have deeply 

 grooved margins, but the exact appearance varies with the angle 

 at which they are viewed. Whether the appearance be that of a 

 ring or of discs with deeply grooved margins, it is in my opinion 

 purely an optical effect arising from the mutual interference of 

 the light rays from the two wreaths of cilia. 



The high under lip is unusually flat and inconspicuous ; the 

 lateral margins of the mouth are scarcely thickened and the 

 mouth cavity is small as compared with that of other Philo- 

 dinidae. When feeding the lumbar plicae are well marked. 



The foot represents about one-ninth of the total length. It 

 has four joints, the first having dorsally a distinct thickening of 

 the hypodermis. 



In the confinement of a small cell H. torquata proved only 



