94 BULIMULUS-N^ESIOTUS. 



closer on the second whorl. Spire straightly conic, the apex very 

 obtuse. Whorls 5*, nearly flat, the last one not more rapidly de- 

 scending than the rest. 



Aperture ovate, one-half the alt. of the shell, vertical, light brown 

 inside with a faint, narrow, light band at position of the periphery, 

 and white within the lip-edge; outer lip obtuse and rather thick, not 

 expanded ; columella with an oblique fold above, the coluraellar 

 margin well dilated, rounded. Alt. 29, diam. 16 mill.; alt. of aper- 

 ture 14J mill. 



Peru. 



Bulimulus sarcoehrous PILSBRY, Proc. Acad. Nat. Sci. Phila., p. 

 21, Feb. 23, 1897. 



Closely allied to the preceding species ; but the spire is more 

 slender, the umbilicus larger, surface less malleated and the colum- 

 ellar fold more conspicuous. The apical riblets are finer and closer, 

 less coarsely granulated on the second whorl. 



Subgenus NAESIOTUS Albers, 1850. 



NoBsiotus ALBERS, Heliceen, p. 162, 1850. Type B. mix. BALL, 

 Proc. Acad. Nat. Sci. Phila., 1896, p. 426. Ehaphiellus PER.. Ver- 

 such einer Anordnung der Heliceen nach natiirlichen Gruppen. 

 Malak. Blatter, II, p. 160, 1855. Type B. achatinellinus. MAR- 

 TENS in Albers, Ed. ii, p. 238, 1860 (Sect. Bulimini). Omphalo- 

 styla H. & A. ADAMS, Gen. Rec. Moll., ii, p. 161, 1855 ; not of Schlue- 

 ter, Syst. Verz., p. 7, 1838. Nesiotes MARTENS, in Albers, ed. ii, pp. 

 220-21, ISQO.Nesiotus CLESSIN, in Pfeiffer, Norn. Hel. Viv., p. 254, 

 1881. Ataxus sp. CLESSIN, op. cit., p. 253. Pelecostoma REIBISCH 

 {ex parte) in Isis, Abh. 3, p. 25, 1892. 



Perforate or rimate Bulimuli with vertically ribbed or striate 

 nepionic whorls, the contour varying from ovate to slender and 

 turrited, surface wrinkled or nearly smooth, generally with spiral 

 strise ; aperture ovate or irregular ; peristome varying from simple 

 to expanded, sometimes with dentiform callosities; the columella en- 

 tire or truncate. Type B. nux. 



Distribution, Galapagos Islands. 



The land shells of the Galapagos Islands have recently been 

 elaborately treated of by Dall (Insular Land Shell Faunas, etc., 

 Proc. Acad. Nat. Sci. Phila., 1896). In the following pages his con- 

 clusions have been adopted, so far as the scope of the Manual ad- 



