204 MOLLUSKS FROM NORTH LABRADOR. 



AQUILONARIA, n. g. 



Shell Lioplaciform, more or less membranous, thin, imperforate, with- 

 out sculpture, but with a rough, transversely shaggy epidermis. Oper- 

 culum subspiral, with a raised subspiral rib on the inner side. Animal 

 much like Litorina with entire sole, short and peculiar radula (see de- 

 scription of the species), tissues soft and very gelatinous, with a pro- 

 fusion of tenacious mucus. There is no jaw, the animal is phytopha- 

 gous. The mantle edge is plain, there are no opercular appendages, 

 and the females are oviparous. 



Aquilonaria Turneri, n. s. Plate III, figs. 1, 2, 3. 



Shell globose-conic with five and a half full and rounded whorls reg- 

 ularly increasing. Shell substance white, extremely thin, and wanting 

 near the aperture; covered with a thick, shaggy, more or less hairy, 

 transversely rugose epidermis of a brownish color, of which the outer 

 and anterior margins of the aperture are chiefly formed. This is tough 

 and flexible in life, but dries out of shape when desiccated ; sutures 

 with a narrow channel except in the last whorl where the channel 

 gradually becomes obsolete ; last whorl forming more than two-thirds 

 of the shell ; aperture ovate, margin thin, not reflected ; columella 

 smooth, thin, rounding gradually into the anterior margin ; inner lip 

 without callus; base rounded, full, without any trace of an umbilicus. 

 Operculum thin, brownish, with about three whorls, slightly transversely 

 undulate and longitudinally finely striate ; on the inner side a well- 

 marked raised rib gyrates with the whorls near their inner edge, but 

 does not quite reach the anterior margin of the operculum. Jaw none, 

 radula short (about 4.00°^™), small, with seven longitudinal and about 

 fifty transverse rows of teeth. Ehachidiau tooth recumbent, broad, 

 short, with a larger median and two distinct lateral cusps, beside (on 

 each side) two less evident waves on the cutting edge. First lateral 

 broader than long, the base with two radiating ridges, the inner one 

 supporting four distinct cusps, the outer one with its cutting edge 

 merely obscurely waved ; second lateral, narrower, witli four strong- 

 cusps ; outer lateral slender with a spatulate base and simple recurved 

 cutting edge. Soft parts very gelatinous and giving out a gelid mucus 

 very abundantly when the preserved animal was soaked in water for 

 dissection. Foot short, broad, bluntly rounded behind, in front squar- 

 ish, the anterior edge bilamellate, the incision triangular with its apex 

 beneath the muzzle in the median line; the upjier surface over this 

 triangle darkly pigmented, the rest of the outer surface of the animal 

 rina^ eyes large and very black ; mantle margin smooth ; opercular 

 waxen white; muzzle short, stout, subcylindrical ; tentacles as in Lito- 

 lobe without ai^pendages ; sole without any median division as far as 

 could be detected. 



