Flammulina.] GASTROPODA. 673 



spiral lines, visible only under a powerful lens. Colour light greenish- 

 yellow above, base more whitish. Epidermis thin, transparent, 

 polished. Spire very low, broadly convex, its height not quite half 

 that of the aperture. Protoconch flat, not marked off from the suc- 

 ceeding volutions. Whorls 4|, the last two more rapidly increasing 

 than the others, convex, periphery acutely rounded ; base more 

 flattish. Suture lightly impressed, margined on the outer side. Aper- 

 ture somewhat oblique, ovately lunate, broader than high. Peristome 

 thin and sharp, straight, retractive from the suture to the base. Outer 

 lip very sharply rounded. Columella very short, arcuate, slightly 

 reflexed above. Umbilicus open, perspective, about one-quarter of 

 the greatest diameter. |p. | 



Diameter Maj., 8 mm. ; min., 6-5 mm. : height, 3-5 mm. Aper- 

 ture Height, 2-5 mm. ; breadth, 3-5 mm. 



Jaw membranous, slightly arcuate, with numerous vertical plaits 

 indenting the cutting-edge. 



Radula having the formula 140 x 17 + 16 + 1 + 16 + 17. Central 

 tooth with a stout mesodont ; the first laterals similar to the central, 

 but in the outer teeth the mesodont is becoming broad and short, and 

 a small ectodont appears ; marginals tricuspid, the median cusp 

 strongest. 



Type in my collection. 



Hob. Head of Staircase Creek, 5,300 ft. altitude, on Nerger Range, 

 Canterbury, in slush of snow, hundreds together (G. F. Roberts) ; 

 March, 1884. 



'2. Flammulina Chiron, Gray, 1850. Plate 26, fig. 13, a, b. 



Zonites Chiron, Gray, P.Z.S., 1849 (1850), 160; A.M.N.H. (2), vii, 66. 

 Helix Chiron, Gray : Pfeiffer, M.H. Viv., iii, 94 ; Reeve, Conch. Icon., 

 vii, pi. 131, f. 797. H. (Paryphanta) Chiron, Gray: Hector, Cat. Land 

 Moll. N.Z., 10. Nanina (Paryphanta} Chiron, Gray : Pfeiffer, Nomencl. 

 Hel. Viv., 35. Paryphanta Chiron, Gray : Hutton, M.N.Z.M., 23. 

 Amphidoxa Chiron, Gray : Hutton, T.N.Z.I., xvi, 199 ; Suter, T.N.Z.I, 

 xxiv, 289, pi. 20, f. 10. Elcea Chiron, Gray : Tryon, Man. Conch. (2), i, 

 129, pi. 26, f. 19. Flammulina Chiron, Gray : Hedley and Suter, P.L.S. 

 N.S.W. (2), vii, 644 ; Suter, J. de Conch., xli, 239. 



Shell small, depressed, arcuately plaited or ribbed, umbilicated, 

 shining, thin and fragile, pellucid. Sculpture on the post-nuclear whorls 

 consisting of arcuate slightly retractive plaits or sharp membranous 

 riblets, 3 to 4 per millimetre, the interstices with a few growth-striae 

 and sometimes indistinct microscopic fine and close spiral lines. 

 Colour fuscous-olive, sometimes with light-brown simple or zigzag 

 bands following the direction of the riblets. Epidermis very thin, 

 transparent, and glossy. Spire very little elevated, nearly flat. Proto- 

 conch of 1 smooth convex whorl. Whorls 3 to 3J, rather convex, 

 rapidly increasing, the last subdepressed, periphery rounded ; base 

 convex. Suture well impressed. Aperture a little oblique, sublunately 

 rotund. Peristome thin, the right margin somewhat bent backwards. 



22 Moll. 



