HELIX-THELIDOMUS. 67 



blunt tooth near the insertion, and is broad and conspicuously trun- 

 cate where the base joins the outer lip. 



Alt. 24, diam. maj. 36, min. 28 mill. 



H. rangelina PFR., Malak. BL, 1854, p. 157, 189, t. 2, f. 1-3. and 

 Novit. Conch,, p. 184, t. 50, f. 1-3. 



This is a well-marked species, quite distinct from the preceding 

 and following forms. The shape is usually more conical than the 

 figures on pi. 2 show it. The base of the aperture bears a very 

 heavy callus plate, which is strongly truncate at its outer termina- 

 tion, and in adults bears an incurved obtuse tooth near the insertion. 

 The face of the peristome in old specimens is very convex and heavy. 

 The aperture is often more oblique than the figures show it. 



H. TRINITARIA Gundlach. PL 17, figs. 38-42. 



Imperforate, depressed-conoidal, straw-colored, finely obliquely 

 costulate-striate, the costulse smooth, not bifurcating, interstices 

 smooth or nearly so, the base smooth, glossy ; spire low conoidal, 

 apex obtuse, smooth, sutures well impressed ; whorls 4, moderately 

 convex, rapidly increasing, the last rounded, somewhat tumid 

 beneath, rather abruptly, deeply deflected anteriorly ; aperture 

 extremely oblique, truncate-oval; peristome expanded, thickened; 

 baso-columellar margin straight, flat, with a blunt tooth near the 

 insertion of the collumella ; not truncated below, passing into the 

 outer margin in a curve. Alt. 24, diam. maj., 35, min, 29 mill. 



Trinidad, Cuba. 



H. trinitaria GUNDL. mss-, PFR., Malak. Bl, 1858, p. 176, and 

 Monogr. v, p. 287. 



This species has the form, size and sculpture of H. rangelina. It 

 differs from that form in having a narrower columellar margin, not 

 in the least truncated where it joins the outer lip, and having above 

 near the insertion an obtuse tooth. It' is more densely finely sculpt- 

 ured than most specimens of H. auricoma, and has a smaller 

 aperture ; and trinitaria is different also, in the distinct tooth near 

 the insertion, the only projection on the upper edge of the baso- 

 columellar margin. 



H. BARACOENSIS (Gutierrez) Poey. PI. 2, figs. 13-15. 



Imperforate, depressed, rather solid, straw-colored or russet, nearly 

 lusterless above, shining beneath ; spire short, low-conical, first 1 

 whorls white, glossy, the remainder coarsely costulate-striate, inter- 

 stices more or less transversely wrinkled or rugose, the costulse 



