242 TORNATELLIDES OF HAWAIIAN ISLANDS. 



oblique folds. Peristome simple, erect, outer margin convex, 

 columellar margin somewhat reflexed over the narrow um- 

 bilicus. Umbilicus minute, circular. Length 2.8, diam. 1.5, 

 axis of apert. 1.3, par. lam. 0.16, umb. 0.23 mm. 



West Maui : Maunahooma near Lahaina (Cooke) . Type no. 

 14113 Bishop Museum. 



1 This species is closely related to T. brunneus of Oahu but 

 the spire is broader with more convex outlines, the base is 

 more attenuate and the whorls are more loosely coiled. From 

 the other species from Maui T. bellus differs by its more atten- 

 uate base, long and narrow aperture, etc. The umbilicus is 

 narrow and compressed. The measurement above is across 

 the longer diameter. The columella, viewed from below, is 

 flexuous. The two columellar folds extend nearly to the mar- 

 gin. There is only a single immature specimen in the series. 

 It has slightly over 5 whorls. The parietal lamella is 0.2 mm. 

 in height. The columellar folds are rather large and parallel. 

 The upper is 0.12, the lower 0.16 mm. in height. 



47. T. PLAGIOPTYX Pilsbry & Cooke, n. sp. PL 53, figs. 1, 2, 3. 



The shell is ovate-pyramidal, umbilicate, the umbilicus mod- 

 erate, but reduced to a perforation aibove the last whorl. Out- 

 lines of the spire straight, the apex obtuse. Whorls 5%, 

 rather strongly 'convex. Brown, with irregular white lines 

 due to erosion of the cuticle. Parietal lamella moderate, nearly 

 a half-whorl long. Columellar margin dilated. Columella 

 bearing two small, equal, rather strongly oblique lamellae, 

 which do not reach the expanded edge in adult shells. Length 

 3.4, diam. 1.9, aperture 1.4 mm. 



Molokai : Western ravine of Kamalo, near the old ditch 

 trail (Cooke & Pilsbry). Type no. 112533 A. N. S. P., cotype 

 in B. P. B. Mus. 



This is a larger, broader shell than T. euryomphala or T. 

 macroptychia, with the parietal lamella lower and the colu- 

 mellar folds more slender. In the immature stages they reach 

 to the margin of the columellar lip. It is a more robust shell 

 than T. lellus, with more convex whorls; but the two are 

 closely related. 



