HELIX-PA RTHEN A. 73 



H. DILATATA Pfeiffer. PI. 19, figs. 55, 56. 



Imperforate, globose or bubble-shaped, thin, light yellow or yellow- 

 ish-brown, unicolored (save for oblique brownisn streaks), or 

 encircled by few or numerous fine undulating or broken lines of 

 brown ; surface apparently nearly smooth, with slight incremental 

 wrinkles, but under a lens the penultimate and part of the last whorl 

 are seen to granulate, the granules not extending far below the 

 suture, wanting on the middle and base of the body-whorl ; spire 

 short, small, apex obtuse, whitish ; whorls 3J to 4, rapidly increasing, 

 the last very wide, globose, gently and very slightly descending 

 anteriorly ; aperture large, rounded-oval ; peristonie narrow, a trifle 

 thickened, upper, outer and basal margins nearly equally curved, 

 colimiella concave, inserted vertically, dilated. 



Alt. 27, diam. 28-30 mill. 



Hayti. 



H. dilatata PFR., P. Z. S. 1345, p. 42, and Conchyl. Cab. t. 152, f. 

 13, 14. REEVE, Conch. Icon. f. 213. 



This shell has the form of H. (Pomatia) aperta of Southern 

 Europe. The aperture is larger than in H. undulata, the columella 

 inserted more vertically, and the whole shell more bubble-like. Like 

 the preceding several species, this form is seen under a strong lens to 

 be covered with a more or less distinct, excessively minute sculpture 

 of oblique corrugations or granules. 



*** 



Shell dark colored, generally chestnut or chocolate, with darker 

 longitudinal streaks ; not distinctly spirally fasdate. 



H. CORNUMILITARE Ferussac. PI. 7, figs. 61, 62. 



Imperforate, very large, depressed-globose, solid, opaque, chestnut- 

 colored, with darker oblique streaks, and behind the aperture 

 mahogany-colored and very glossy ; the surface covered with an 

 excessively minute decussation of spiral and oblique microscopic 

 lines ; spire conoidal, obtuse, whorls 5, moderately convex, the first 

 2 densely granulated, whitish, the remainder rather coarsely oblique- 

 ly marked by wrinkles of increment, the last encircled by one or 

 several very shallow sulci in the region of the periphery, anteriorly 

 deflexed ; aperture oblique, bluish within, rounded-subquadrate ; 

 peristome expanded, thickened within, white, upper and lower mar- 



