lo Hawaiian Species of Helicina. 



Helicina rotelloidea Migh. 



Fig. 9. 

 Helicina rotelloidea Mighels, Proc. Bost. Soc, ii, 1845, P- ^9- 



The shell is depressed, with a low conoidal spire and a well 

 rounded periphery, thin, nearlj' smooth, dull, under a lens show- 

 ing minute lines of growth and two or three faint spiral lines above 

 the periphery. Color a uniform dull cinnamon more reddish on 

 the spire (sometimes of a uniform light greenish yellow). vSpire 

 convexl}- conoidal, apex subacute. Suture simple, well impressed. 

 Whorls 3^, distinctly convex, at first slowl}' and regularly then 

 rapidly increasing, the last wide, well rounded, convex below the 

 periphery, hardly descending in front. Aperture quite oblique, 

 semicircular, not contracted ; outer lip thin. Callus thin, becom- 

 ing thick and whitish about the axis, the outer portion transparent, 

 of the color of the shell, very minutely punctate. Operculum very 

 thin, whitish, minutely punctate. Maj. diam. 3.0, total length 

 2.0 mm. 



Oahu : Nuuanu (Cooke). This species is somtimes terrestrial 

 in habitat. It is usually found on growing plants two or three feet 

 above the ground. 



Type of the above description, No. 14,907, Bishop Museum. 



Mighels' type is probably lost. Unfortunately the species is 

 insufficiently described and there are no figures of authentic speci- 

 mens of this species. Pfeiffer's figures (Conch. Cab., Helicina, 

 pi. iii, figs. 40-43) undoubtedly refer to H. broiiniana Phil. 

 Mighels' measurements (2.5-5.8 mm.) include at least two spe- 

 cies, the smaller of which has been chosen to represent the species. 



The specimen selected differs from his description in the ab- 

 sence of "obscure light spots." These are, however, found in 

 other specimens from another part of Xuuanu Valley. 



H. rotelloidea is characterized by its small size, convex whorls 

 and rounded periphery'. 



Helicina nuuanuensis, n. sp. 



Fig. 10. 



The shell is subgloboseh' conic, slightl}^ angular at the peri- 

 phery, thin, nearly smooth, minutely transversely striate and with 

 four or five fine raised spiral striae, of w^hich two are above, the 



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