ANTILLEAN OBELISCUS. 263 



"This species is readily distinguishable from terebraster 

 and homalogyra, which have the columefLla similar, by the 

 much narrower, quite regularly descending whorls" (Pfr.). 



Pf eiffer 's original figure is copied, figs. 7, 8, and two speci- 

 mens are drawn, figs. 9, 10. These measure : 



Length 17, diam. 4, aperture 4 mm.; whorls 10. 



Length 17.8, diam. 3.8, aperture 3.9 mm.; whorls 10%. 



The apex is small, 1 mm. in diameter at the second whorl, 

 being smaller than in terebraster, and the spire is noticeably 

 contracted above. 



21. 0. HOMALOGYRA (' Shuttl. > Pfr.). PI. 30, figs. 13, 14, 15. 



Shell imperforate, cylindric-turrite, striatulate, slightly 

 shining, diaphanous, whitish-hyaline. Spire long, rather ob- 

 tuse; suture light, submarginate. Whorls 8, slowly increas- 

 ing, the upper four raither convex, the rest flattened, last 

 whorl two-sevenths the total length, slightly tapering basally. 

 Columella callous, somewhat twisted, receding. Aperture 

 oblique, sub-semioval ; peristome simple, unexpanded, the 

 right margin receding basally, forming an angle with the 

 columella. Length 16, diam. 4, aperture 4.5x2 mm. (Pfr.). 



Central Cuba: near Trinidad, at the sugar plantation 

 "Magua" and at the "Sitio del Quern-ado" (Gundlach), and 

 on the hill "La Vigia" (Pilsbry) ; Sancti Spiritus around 

 limesitone rocks; on the hillside west of Matanzas (Pilsbry). 

 Also reported from Almendares and Fermina. 



Bulimics homalogyrus Shuttleworth mss., PFR., Conchy!. 

 Cab., p. 91, pi. 31, f. 9, 10; Monogr., iii, 392; Malak. BL, 

 1857, iv, p. 107. 



The habitat was originally unknown, Tbut as Trinidad speci- 

 mens are typical, that may be considered the type locality. 

 It occurs on La Vigia rather sparingly under stones. It is 

 the common and characteristic Obeliscus of central Cuba. 



Fig. 13 is a copy of the original illustration; figs. 14, 15 

 represent Trinidad specimens of the maximum size, enlarged 

 to double natural size, showing the more slender and the 

 wider phase. The suture is narrowly but deeply incised. 

 The glossy surface is delicately but distinctly arcuate-striate, 



