1887.] NATURAL SCIENCES OF PHILADELPHIA. 145 



Aricalus Oparicus, Pfeiffer, 1. e. 



A few small examples found on the margin of a swamp at Upolu. 

 It occurs in the Tonga and Viti Islands and ranges west as far an 

 the East Indies. Mo relet records it from the island of Mauritius. 



A small species, 9 to 16 mill, long, of a slender fusiform shape, 

 smooth, shining surface, acute conical spire (which is frequently 

 truncated by erosion); color white beneath an epidermis which va- 

 ries from pale olivaceous-horn color to chestnut-black. The body 

 whorl is narrow, usually longer than the spire, attenuated or round- 

 ed at the base, and the collimella is furnished with two, small, ap- 

 proximating, oblique folds. A compressed subtransverse plait on 

 the lowei- part of the parietal region. 



S. semisculpta, II. and A. Adams. 



Ellohium semiscidptuni, H. and A. Adams, Proc. Zool. Soc, 1854, 

 p. 9 ; Gen. Moll., ii, p. 237. 



Aurkula semisculpta, Pfeiffer, Syn. Auric, no. 139 ; Mon. Auric, 

 i, p. 136 ; Novit, Conch., i, p. 39. pi. 10, figs. 7-9. Gassies, Faun. 

 Nouv. Caled., p. 70, pi. 3, fig. 11. Schmeltz, Cat. Mus. Godefl?!, v, 

 p. 88. 



Auriculus .seiisct(^jo^u.s, Pfeiffer, Mon. Pneum. (Auric), iv, p. 359. 



A few dead specimens of small size found on the margin of a 

 mangrove swamp at Upolu. It is also common at Wallis Island 

 and very abundant and of large size at the Viti group, where they 

 were found buried in rotten logs in swamps. 



This species varies considerably in shape, thickness, and in size, 

 ranging from 12 to 30 mill, in length. The surface is shining, longi- 

 tudinally striated, and the upper j)ortions of the whorls are sculp- 

 tured by crowded S2)iral rows of minute granules, which, in the 

 adult sometimes cover the whole surface of the body-whorl. The 

 shape of the shell varies froin oblong-ovate to oblong-turreted, the 

 spire more or less produced, and the color is white beneath a ful- 

 vous-yellow or yellowish-horn colored epidermis. The parietal re- 

 gion exhibits a prominent, compressed, oblique fold and just beneath 

 is a .smaller and more vertical one on the columella. 



TRTJNCATELLA, Risso. 

 T. valida, Pfeiffer. 



Truncatella valida, Pfeiffer, Zeit. Malak., 1846, p. 182; Mon. 

 Auric, (appendix), i, p. 184. Jay, Cat. Shells, 1854, p. 253. Kuster, 

 Mon., p. 11, pi. 2, figs. 7, 8, 19-21, 23. H. and A. Adams, Gen. Moll, 



