OCR Text |
Show ^887.] MOLLUSKS OF THE VITI ISLANDS. 295 Genus PLECOTREMA, H. & A. Adams. 1. P L E C O T R E M A SOUVERBIEI, Montrouzier. Plecotrema souverbiei, " Montrouzier," Souverbie, Journ. de Conch. 1862, p. 246, pl. 9. fig. 12 ; Gassies, Faune Nouv. Cale'd. p. 67, pl. 6. fig. 23 ; Pfeiffer, Mon. Pneum. (Auric.) iv. p. 343. Plecotrema turrita, Garrett, Proc. Phil. Acad. Nat. Sci. 1873, p. 235, pl. 3. fig. 68. Not uncommon under stones a little below high-water mark on the east end of Taviuni. It also inhabits N e w Caledonia. This remarkable species is easily recognized by its ovate-conical form, scalariform spire, corneous or dull fulvous colour, subper-forated and angulated base. The sculpture consists of numerous, small, crowded, granulated spiral ridges, with the intermediate grooves crossed by sublatninated strife. There is a prominent crestlike varix just behind the peristome, which latter is acute, continuous, and slightly porrected. Parietal region with a superior nodiform tooth beneath, of which there is a simple acute plait. Columellar fold small and nearly transverse. Outer lip labiate within and bidentate. Length 4 | millim. Very closely allied to, if not identical with, P. bella, a Philippine species. 2. PLECOTREMA HIRSUTA, Garrett. Plecotrema hirsuta, Garrett, Amer. Journ. Conch. 1872, p. 219, pl. 19. fig. 2 ; Schmeltz, Cat. Mus. Godeff. v. p. 87 ; Pfeiffer, Mon. Pneum. (Auric.) iv. p. 348. Abundant in the same station and locality as the preceding species. An imperforated, solid, acutely-ovate, corneous species, with spiral rugose lirae, 16 to 18 on the body-whorl, garnished with short, deciduous, curved bair-like setae. The intervening sulcations deep, narrower than the lirations, and crossed by sublaminated striae. There is a stout obtuse varix just behind the peristome, and the dentation, excepting the lower parietal fold, which is bifid, does not differ from the preceding species. Length 5 to 7 millim. 3. PLECOTREMA OCTANFRACTA (Jonas). Pedipes octanfracta, Jonas, Zeit. Malak. 1845, p. 160. Plecotrema octanfracta, Jeckeli, Nachr. Malak. Ges. 1872, p. 65 ; Pfeiffer, Mon. Pneum. (Auric.) iv. p. 346. Plecotrema clausa, H. & A. Adams, Proc. Zool. Soc. 1853, p. 121 ; Gen. Moll. ii. p. 241 ; Pfeiffer, Syn. Auric, no. 101 ; Novit. Conch. i. p. 15, pl- 5- figs- 9-11 ; Mon. Auric, i. p. 103 ; Pease, Proc. Zool. Soc! 1871, pp. 459, 477; Paetel, Cat. Conch, p. 144; Schmeltz, Cat. Mus. Godeff. v. p. 87. Plecotrema consobrina, Garrett, Proc. Phil. Acad. Nat. Sci. 1873, p. 236, pl. 3. fig. 69. Not uncommon under stones a little below high-water mark at Kioa |