Rissoina.] GASTROPODA. 225 



slightly convex. Protoconch small, flatly convex, smooth. Whorls 5, 

 convex, regularly increasing, the last high, rather ventricose and 

 slightly contracted below ; base convex. Aperture oblique, oval, 

 jingled above. Pcristomc continuous, not thickened. Basallip slightly 

 expanded. Columella oblique, a little arcuate, subtruncate. Inner 

 Up but little reflexed. Operculum unknown. 



Diameter, 1-7 mm. ; height. 2-8 mm. 



Animal unknown. 



Type in my collection. 



Hob. Hohoura Bay (Roger Buddie). 



11. Rissoina limbata, Button, 1883. Plate 13, fig. 18. 



Cingula limbata, Hutt., N.Z.J.S.. i, 477 ; T. N.Z.I., xvi. 214. Rissoa limbata, 

 Hutt.. P.L.S. N.S.W., ix, 941. R. (Set-id) limbata, Hutt., Man. Conch. 

 (1), ix, 355, pi. 71, f. 98. Phasianella limbata, Hutt. : Suter, P. Mai. S., 

 iii. 8. Rissoina (Eatoniella) limbata, Hutt. : Webster. T.N.Z I., xxxvii, 

 278, pi. 10, f. 8, 8a (operc. and dentition) ; Suter, T.N.Z.I., xxxviii. 327. 



Shell very small, elongately conical, slightly rimate, smooth, and 

 polished. Colour ashy-brown, usually with a posterior row of white 

 spots and brown zigzag lines at the suture ; last whorl often with 

 angulated brown and white markings around the periphery. Spire 

 elevated conic, higher than the aperture, outlines straight. Protoconch 

 minute, globose, white, of 1^ smooth and convex whorls. Whorls 5-6, 

 the last rather large in proportion, flatly convex ; base rounded. 

 Suture impressed. Aperture ovate, angled above. Peristome con- 

 tinuous, sharp, lightly callous inside, somewhat effuse at the base. 

 Columella vertical, arcuate, a little callous and reflexed. Umbilicus 

 indicated by a narrow chink. Operculum horny, with a claviform 

 process (Webster, T.N.Z. I., xxxvii, pi. 10, f. 8a). 



Diameter, 1-5 mm. ; height, 2-7 mm. 



Dentition. Webster, T.N.Z.I., xxxvii, 278, pi. 10, f. 8. Very 

 much like that of R. olivacea, Hutt. 



Type in the Canterbury Museum, Christchurch. 



Hab. Auckland, type (T. F. Cheeseman) ; Cook Strait ; Te One- 

 poto, near Lyttelton ; Taumaki Island, South Island, in 10 fathoms 

 (Captain Bollons) ; Dusky Sound, in 30 fathoms (R. Henry). 



12. 'Rissoina olivacea, Hutton, 1882. Plate 13, fig. 19. 



Dardania olivacea, Hutt., T.N.Z.I., xiv, 1881 (1882), 147, pi. 1, f. K, 1-4. 

 Rissoina olivacea, Hutton, P.L.S. N.S.W., ix, 940; Suter, P. Mai. S., 

 iii, 7; Webster, T.N.Z.I., xxxvii, 279, pi. 10, f. 9a (opercul. and teeth 

 of radula). Jeffreysia (Dardania) olivacea, Hutt., Man. Conch. (1). ix, 

 397, pi. 60, f. 95. 



Shell very small, ovate, imperforate, rather solid, smooth. There 

 is no sculpture except fine growth -lines. Colour olive-brown when 

 alive, purplish -black when dry. Spire elevated conical, higher than 



8 Moll. N.Z. 



