302 MR. A, GARRETT ON THE TERRESTRIAL [Mar. I , 



It is a long, slender, greyish-white species, with 5 persistent 

 subconvex whorls and a deep suture ; the riblets, of which there are 1 8 

 to 20 on the last whorl, are thin, sharp, and separated by rather wide 

 interspaces. The vertical aperture is obtusely biangulately ovate, 

 and the porrected peristome is continuous, expanded, and slightly 

 reflected. Length 9 millim. 



3. Taheitia arcasiana (Crosse). 



Truncatella arcasiana, Crosse, Journ. de Conch. 18G8, p. 177, 

 1870, p. 107, pi. 7. fig. 13; Mousson, Journ. de Conch. 1870, 

 p. 196; Schmeitz, Cat. Mus. Godeff. v. p. 104; Pfeiffer, Mon. 

 Pneum. iv. p. 20. 



Truncatella alternans, Mousson, in Cat. Mus. Godeff. iv. p. 7G- 



This species (which is unknown to me) was found by Dr. Griiffe in 

 the interior of Vjti Levu. 



Mr. Crosse says it is an elongated, cylindrically-turreted, chalky, 

 dull whitish species, 9 millim. long, with remote riblets, which are 

 sometimes evanescent on the middle of the whorls. The persistent 

 6 whorls are rather convex, the suture is impressed, and the aperture 

 suboval. The peristome is continuous, porrected, and slightly 

 expanded. 



4. Taheitia scalariformis (Reeve). 



Truncatella scalariformis. Reeve, Proc. Zool. Soc. 1842, p. 197; 

 Conch. Syst. ii. pi. 182. fig. 6 ; Pfeiffer, Zeit. Malak. 1846, p. 186 ; 

 Mon. Auric, i, (Appendix) p. 191 ; Jay, Cat. Shells, 1850, 

 p. 252 ; KiJster, Mon. p. 15 ; H. & A. Adams, Gen. Moll. ii. p. 31 ; 

 Schmeitz, Cat. Mus. Godeff. v. p. 104. 



Truncatella truncatula, var., Anton, Verz. Conch, p. 62. 

 Truncatella arctecostata, Mousson, Journ.de Conch. 1869, p. 68, 

 pi. 5. fig. 4, 1870, p. 195; Paetel, Ciit. Conch, p. 117; Schmeitz, 

 ■ Cat. Mus. Godeff. iv. p. 76 ; Pfeiffer, Mon. Pneum. iv. p. 19. 



Taheitia scalariformis, Pease, Proc. Zool. Soc. 1871, pp. 468, 

 477; Journ. de Conch. 1871, p. 92; Martens & Langk. Don. 

 Bismark. p. 60, pi. 4. fig. 1. 



Prof. Mousson's original description of T. arctecostata was drawn 

 up from specimens of T. scalariformis collected by me at Anaa, 

 Paumotu Islands. The same, or a very closely allied, species was 

 subsequently discovered by Dr. Griiffe on Viti Levu, and referred by 

 Mousson to T. arctecostata. I have not seen any Viti specimens. 



It is a thin, subpellucid, cylindrically-turreted, yellowish-white 

 or corneous species, with 4 or 5 persistent convex whorls. The 

 riblets are numerous (38 to 40 in the last whorl), very slightly 

 arched, and converging at the base. The aperture is vertical, small, 

 broadly ovate, and the peristome is thin, continuous, and expanded. 

 Operculum typical. Length 6 millim. 



Genus Diplommatina, Benson. 

 1. Diplommatina martensi, H. Adams. 

 Diplommatina (Diancta) martensi, H. Adams, Proc. Zool. Soc. 



