656 GASTROPODA. [Pulmonata. 



interstices minutely reticulated by growth and spiral striation ; the 

 radial sculpture less prominent over the base. Colour yellowish-brown, 

 with radial unequal streaks of rufous. Epidermis very thin and 

 shining. Spire broadly conoidal, of about the same height as the 

 aperture. Protoconch of 1-| smooth and flatly convex whorls. Whorls 

 5 to 6, regularly increasing, flattish, the last sharply keeled ; base 

 convex. Suture much impressed. Aperture broadly subquadrangular. 

 Peristome acute, simple, very thin. Outer lip descending almost 

 straight, angled on meeting the slightly convex basal lip. Columetta 

 oblique, concave, slightly reflexed. Perforation moderate, somewhat 

 perspective, deep. 



Diameter, 7 mm. ; height, 4 mm. (type). 



Jaw arcuate, composed of numerous vertical plaits. 



Radula. Only a very young specimen was at my disposal, and the 

 teeth were not sufficiently differentiated to decide whether the species 

 is a Therasia or Thalassohelix. 



Type in the Mus. Hist. Nat.. Paris. 



Hob. Auckland Islands (Hombron and Jacquinot, Le Guillou, 

 Krone, Professor Benham) ; found under logs. 



Remark. I accept H. & J.'s name because they figured the species. 



Subsp. chathamensis, Suter, 1909. Plate 26, fig. 3. 



Therasia antipoda chathamensis, Sut., P. Mai. S., viii, 1909, 259, pi. 11, f. 20. 



The following characters distinguish the subspecies from tin- 

 species : The radial sculpture consists of less-prominent strise and 

 plications ; the rufous streaks are narrower, more numerous, and often 

 zigzag-shaped ; the whorls are much more convex, the last more or 

 less angled at the periphery, never sharply keeled ; suture deeper ; 

 aperture roundly oval, the outer lip but slightly angled, and the basal 

 lip more convex. 



Diameter Maj., 7-1 mm. ; iriin., 6-5 mm. : height, 4mm. 



Animal unknown. 



Type in my collection. 



Hob. Chatham Islands (Captain Button) ; Stewart Island (C. 

 Traill). 



2. Therasia Celinde, Gray, 1850. Plate 26, fig. 4, a, b. 



Nanina (?) Celinde, Gray, P.Z.S., 1849 (1850), 164; A.M.N.H. (2), vii, i4. 

 Helix Celinde, Gray : Pfeiffer, M.H. Viv., iii, 125 ; Reeve, Conch. Icon., 

 vii, pi. 131, f. 799^. H. (Thalassia) Celinde, Gray : Hector, Cat. Land 

 Moll. N.Z., 16. Nanina (Thalassia] Celind.e, Gray : Nomencl. Hel. Viv., 

 47. Patula Celinde, Gray : Hutton, M.N.Z.M., 6. Charopa (Therasia) 

 Celinde, Gray: Tryon, Man. Conch. (2), ii, 211, pi. 62, f. 41. Therasia 

 Celinda, Gray : Hutton, T.N.Z.I., xvi, 202 ; Hedley and Suter, P.L.S. 

 N.S.W. (2), vii, 644. Flammulinu (Therasia) Celinde, Gray : Suter, 

 J. de Conch., xli, 244 ; Man. Conch. (2), ix, 16. 



Shell small, subperf orate, rather depressed, membranously plaited, 

 thin, pellucid. Sculpture, : Protoconch microscopically rather dis- 

 tantly spirally stria te ; the following whorls with distant membran- 



