234 GASTROPODA. [Pectinibraitchia. 



5. Potamopyrgus spelaeus, Frauenfeld, 1862. Plate 14, fig. 6. 



Hydrobia spelcea, Frfld., V,Z.B.G. Wien, xiii, 1862, 1022 ; xv, 526. pi. 8. 

 Bythinella spelcea, Frfld. : Hutton, M.N.Z.M., 82. Potamopyrgus spelceus, 

 Frfld. : Suter, T.N.Z.L, xxxvii, 266. 



Shell very small, conical, rather solid, subtransparent, faintly 

 shining, smooth, rimate. Colour of type yellowish-white, fresh speci- 

 mens, however, are greenish or brownish yellow, mostly with a thin 

 brown coating. Spire elevated conical, a little higher than the 

 aperture, outlines convex. Protoconch minute, globular. Whorls 5, 

 slightly convex, the last rather large ; base rounded. Suture deep. 

 Aperture oval, angled above, oblique. Peristome continuous, slightly 

 expanded, mostly brown, free above, thence connected with the body, 

 leaving a narrow chink below. Operculum normal. 



Diameter, 1-6 mm. ; height, 3 mm. (type). 



Animal unknown. 



Type in the K.K. Hof museum, Vienna. 



Hob. In caves with Dinornis bones, together with P. Reevei, in 

 Cuming's collection (type) ; salt springs, Te Mahia, Hawke's Bay 

 (A. Hamilton) ; Wanganui River, tidal part (R. Murdoch) ; upper 

 Wanganui River (Cbadwick) ; cold mineral pool, Rotorua (Lady F. 

 Brown) ; Te Aroha, in hot - spring water (C. Cooper) ; Onehunga 

 Springs. 



dbsp. pupoides, Hutton, 1882. Plate 14, fig. 7. 



Potamopyrgus pupoides, Hutt., T.N.Z.L. ~s.iv, 1881 (1882), 146, pi. 1, f. D. H. 

 P. spelceus, Frfld., subsp. pupoides, Hutt. : Suter, T.N.Z.L, xxxvii, 266. 



It is distinguished from the species by its cylindrical form, the 

 much flatter whorls, and the less impressed suture. 



Diameter, 0-9 mm. ; height, 1-5-1-75 mm. 



Dentition. Hutton, T.N.Z.L, xiv, 146, pi. 1, f. H. 



Type in the Canterbury Museum, Christchurch. 



Hob. Heathcote Estuary, type (Hutton) ; Parua Bay, Whangarei ; 

 Onehunga Springs : in brackish water. 



6. Potamopyrgus subterraneus, Suter, 1905. Plate 14, fig. 8. 



Potamopyrgus subterraneus, Suter, T.N.Z.L, xxxvii. 1904 (1905), 267. fig. 

 in text. 



Shell minute, subcylindrical, fragile, opaque-white, smooth. Spire 

 pupoid ; apex blunt. Whorls 5, convex, the last whorl more than 

 half the axis. Suture well impressed. Aperture very oblique, oval. 

 Peristome very thin, membranaceous (specimen apparently not quite 

 adult), continuous. Columella subvertical, slightly callous, very little 

 reflexed. Umbilicus indicated by a narrow chink. Operculum un- 

 known. 



