DRYM^US, SOUTH AMERICAN. 237 



D. CYGNEUS (Philippi). PI. 44, figs. 92, 93. 



Shell broadly perforate, oblong-turrited, densely plicate striate, 

 decussated upon the upper part of the whorls by distant lines ; 

 white. Whorls 6 to 7, a little convex, the last scarcely as long as 

 the spire. Aperture pi riform- ovate ; coluruella slightly twisted, 

 compressed ; peristome expanded, the columellar margin dilated, 

 not closing the umbilicus. Largest specimen measures: Alt. 37, 

 diam. 19 mill.; aperture, measured outside, alt. 19, width 12 mill. 

 (Phil). 



" Lomas de Supe" Peru (Raimondi). 



Bulimus cygneus PHIL., Malak. Bl., xiv, 1867, p. 68. PFR., 

 Novit. Conch., p. 342, pi. 81, f. 3, 4 ; Monogr., vi, p. 57. 



Pfeiffer cites the wrong figures in the Novitates Conchologicse, 

 both in text and on the plate ; also in the Monographia. 



Seems to be near B. membranaceus Phil., but the shell is more 

 solid, the whorls more convex, columellar margin much longer, 

 embryonal whorls very large, etc. 



D. MEMBRANACEUS (Philippi). PI. 44, figs. 90, 91. 



Shell perforate, elongate, subconic, very thin, whitish-hyaline, 

 smooth, under the lens transversely striate, shining. Whorls 7 

 but little convex. Aperture semioval, patulous, shorter than the 

 spire; peristome simply expanded, the right margin arcuate, left 

 margin very broad, reflexed, with the umbilical fissure concealed. 

 Alt. 15, diam. 8 lines. (Phil). 



Habitat unknown. 



Bulimus membranaceus PHIL., Abbild. u. Beschreib. neuer oder 

 wenig gekannter Conchylien, ii, p. 126 [22], Bui., pi. 5, f. 2 (Oct- 

 ober, 1846). PFR., Monogr., ii, p. 102 ; viii, p. 69 (excl. syn.). 

 Not B. membranaceus REEVE, Conch. Icon., pi. 75, f. 544. Not 

 Otostomus membranaceus MARTENS, Binnenmoll. Venezuela's, p. 30. 

 ? ? Bulimulus membranaceus BLD. & BINN., Amer. Journ. Conch, 

 vii, 1872, p. 182. Conf. Crosse and Fischer, Moll. Terr. Mex., p. 

 559, and E. von Martens, Biol. Centr.-Amer., Moll., pp. 223, 224. 



" The contour is lengthened conic, and reminds one of B. pcecilus 

 Orb. and the like. The whorls are very little convex, smooth and 

 glossy, under the lens with finely scratched transverse [spiral] lines, 

 and at the suture fine little folds of the growth-strise. The aperture 

 comprises about three-sevenths the entire length ; the peristome is 



