DRYM^EUS, SOUTH AMERICAN. 195 



36, f. 215. Bulinus hygrohylceus SOWB., Conch, lllustr., f. 62 

 Bulimulus hygrohylceus BECK, Index, p. 63. 



Varies considerably in size and color-pattern ; but the rather nar- 

 row mouth with widely reflexed, recurved, white peristome, solid 

 texture aud finely reticulate surface are more constant. The aper- 

 ture is decidedly produced basally. The whorls of the spire are 

 more convex than in D. marmarinus, which is besides a smoother 

 species, 

 D. COARCTATUS (Pfeiffer). PI. 28, figs. 17, 18 (typical) 19, 20 



(var.). 



Shell rimate-perforate, acutely ovate, solid ; whitish encircled by 

 interrupted bands ; spire conic, acute ; whorls 6?, flattened, the last 

 more convex, as long as the spire. 



Aperture oblong, coarctate, the columella thickened, tuberculate ; 

 peristome broadly expanded, the right margin thickened within, 

 acutely projecting, a little sinuous in the middle, joining the dilated 

 and reflexed coluraellar margin at an angle. Alt. 34, diam. 17 mill. 



Brazil (Castelnau). 



Bulimus coarctatus PFR., P. Z. S., 1845, p. 73 ; Monogr., ii, p. 90 ; 

 Xovit. Conch., i, p. 80, pi. 22, f. 22, 23 ; Malak. Bl. v, 1858, p. 166. 

 HUPE in Castel nan's Exped., Moll., p. 56, pi. 10, f. 4. Not B. coarc- 

 tatus Reeve. 



A form with nearly continuous bands is illustrated by Hupe (see 

 pi. 28, figs. 19, 20), who describes it as whitish with blackish bands 

 varying in width, sometimes interrupted, mainly on the earlier 

 whorls, the last whorl ordinarily with three bands; a wider band 

 bounds the umbilicus. Aperture and peristome white. 



D. SCHMIDTI (PfeifTer). PL 28, fig. 16. 



Shell umbilicate, ovate-conic, ventricose, wrinkle-striatulate, de- 

 cussated with minute impressed spiral lines ; gray-brown marbled 

 with paler. Spire conic, the apex rather obtuse, blackish. Whorls 

 6i, a little convex, the last a little longer than the spire, inflated, 

 somewhat ascending in front, marked here and there with buff 

 streaks and white dots, more distinctly striated and black-banded 

 around the umbilicus. 



Aperture vertical, sinuate-oval, pearly-white inside ; columella 

 obliquely receding ; peristome white, thin, widely expanded, the 

 margins joined by a thick whitish callus, right margin arcuate, 



