HEL1X-PEDINOGYRA. 13 



I have seen but a single specimen of this beautiful and rare 

 species, and that without a cuticle. It differs from H. trisinuata in 

 the higher spire, narrower umbilicus, and in lacking the upper lip- 

 tooth of that species. Young specimens have pretty long bristle-like 

 hairs upon the warts of the surface, which are lost in the adult. 



H. LOXOTATUM Mabille. PL 1, figs. 18, 19, 20. 



Shell widely, deeply umbilicated, destitute of cuticle and color, 

 rather solid, lusterless, covered above and below with a sculpture 

 of large sharp tubercles arranged in rows ; spire plane ; apex small, 

 scarcely projecting; whorls 5-5 J, rounded, narrow, rapidly and 

 regularly increasing, separated by a well-impressed suture ; the last 

 whorl large, above double the width of the preceding one, rounded, 

 compressed below the periphery, convex around the umbilicus, a 

 little descending in front and then abruptly deflexed, free from the 

 preceding whorl, profoundly scrobiculate on the outer, basal and 

 columellar margins behind the lip. The aperture is horizontal, with 

 continuous toothed margins. There is a strong tuberculous but not 

 entering tooth on the parietal wall ; two somewhat entering folds on 

 the outer wall, the upper one pointed, the other large, entering ; and 

 finally a deep-seated columellar tooth. The peristome is thin, well- 

 expanded. Alt. 8, greater diam. 19, lesser 16 mill. (Mabille.) 



Tonquin. 



Helix loxotatum MABILLE, Moll. Tonk. diagn., p. 5, May, 1887. 

 Prodostoma loxotatum MAB. Bull. Soc. Mai. France iv, p. 102, t. 1, 

 figs. 1, 2, 3. (Received at Philadelphia Jan. 10, 1888.) 



Allied to H. trisinuata, but with wider last whorl, wider umbilicus, 

 and differently shaped aperture. 



H. HENSANIENSIS Gredler. 



The description of this form is not now accessible to me. 



Subgenus XVI. PEDINOGYRA Albers, 1860. 



Pedinogyra ALBERS, Die Heliceen, 2d ed., p. 162 (type H. cun- 

 ninghami Gray). PFEIFFER, Noment. Hel. Viv., p. 184. Macro- 

 cyclis BECK, and of Pfeiffer and Cox, olim. 



Shell large, discoidal, solid, opaque and colored; very broadly 

 umbilicated ; spire very low ; whorls 5-6, the last very large, deeply 

 deflexed anteriorly ; aperture oblong, nearly horizontal, lip a trifle 

 expanded ; base compressed behind the baso-columellar lip. Type, 

 H. cunninghami Gray. 



