MEGASPIRA. 185 



less strongly developed subcolumellar lamella within, and 

 different shaped basal transverse barriers. M. elata Gld. 

 differs by its somewhat more numerous whorls and much 

 lower transverse barriers, which are not hooked, and espec- 

 ially by its finer external sculpture. The original description 

 of elatior follows: " Shell cylindric, long, apex obtuse, thin, 

 pellucid; longitudinal striae oblique, deep and close. Whorls 

 16, rather flattened, separated by a deep suture, sensibly de- 

 creasing, the last whorl somewhat swollen; apex obtuse. 

 Aperture semiovate, expanded, provided with two folds: a 

 fold on the columellar plate [parietal wall] spirally passing 

 into the aperture, and a fold on the left margin [columella], 

 divided by a groove. Peristome subreflexed on the right 

 margin, the left margin expanso-reflexed, partially covering 

 the umbilical crevice. Color brownish white, with some lon- 

 gitudinal chestnut streaks. Length 1 inch, 4^ lines; width 

 4 lines. Habitat with the preceding " [middle eastern prov- 

 inces of Brazil] . 



The typical form of M. elatior is described above, and illus- 

 trated in figs. 9, 10. Fig. 10 represents the lower three whorls 

 from the back. 



2a. Var.robusta Pilsbry, n. v. PL 28, fig. 7; pi. 29, fig. 11. 



Shell larger, with much more widely open umbilicus; colu- 

 mella distinctly trilamellate ; scallops of the columellar lamella 

 bent downward somewhat. Sculpture as in typical elatior. 

 Length 44, diam. above aperture 9 mm., whorls 19 ; length 38, 

 diam. 8.6 mm., whorls 16%. 



This variety approaches M. ruschenbergiana in size and in 

 its open umbilical chink, but differs in internal structure. 

 The teeth of one of our specimens were figured under the 

 name Megaspira elata Gld., in Proc. Acad. Nat. Sci. Phila., 

 1898, pp. 283, 285, pi. 17, f. 1. 



26. Var. gracilis Pilsbry, n. v. PL 28, fig. 8 ; pi. 29, figs. 14, 15. 



With the typical form there are specimens in the collection 



of the Academy which differ by their more slender and 



cylindric shape, more numerous whorls and slightly smaller 



