142 TORNATELLINA. 



to us by the original description only. It is not certainly 

 known to belong to the bilamellata group. 



Group of T. perplexa. 



Small, delicate species, very similar to those of the section 

 Tornatellinops, from which they differ by having an acute 

 lamella superposed upon the weak columella fold. They differ 

 from Lamellina by lacking well-developed vertical ribs within 

 the palatal wall, yet in some species the two groups are 

 scarcely distinguishable. The delicate palatal denticles are 

 often absent in adult shells. The neanic stage is like the adult 

 in perplexa and nitida. 



5. T. BALDWINI Ancey. PI. 35, figs. 3, 4; pi. 40, fig. 13 ; pi. 42, 

 figs. 1, 2. 



Shell oblong-ovate, imperforate, thin, pellucid, corneous, 

 glossy, under a lens slightly striatulate. Spire conoid, a little 

 longer than the aperture, the summit subacute. Whorls 4, 

 convex, rapidly increasing, the last oblong. Aperture acutely 

 oblong-ovate, hardly compressed outwardly, bearing a rather 

 minute revolving lamella on the parietal wall. Columella 

 thickened, whitish, toothless, obliquely twisted, continued into 

 the anterior margin. Length 2.5, diam. 1.5, length of aper- 

 ture 1.2 mm. (Ancey). 



Kauai (Baldwin, Cooke) ; Oahu: Manoa (Baldwin), Tan- 

 talus (Baldwin, Cooke), Nuuanu (Cooke), Waianae Mts. 

 (Perkins, Cooke); Maui : Kaupakalua and Keanae (Bald- 

 win) ; Hawaii (Thaanum). In the pleistocene of Oahu at 

 Kaelepulu, Kailua, Laie and 1% miles W. of Kahuku. 



Tornatellina baldwini ANC., Bull. Soc. Malac. France, vi, 

 1889, p. 238 ; Journ. de Conchyl., li, 1903, p. 296, pi. 12, figs. 

 1, 2. SYKES, Fauna Hawaiiensis, Moll., p. 380. 



i ' The specimen from Oahu which served for the description 

 was not fully developed. In the adult stage the species is a 

 little larger, with one whorl more, and the spire is a little 

 longer. The characters of the aperture remain the same" 

 (Ancey). Mr. Ancey 's figures are copied, pi. 35, figs. 3, 4. 



This species and T. mcgregori are more obese than other 



