UNIVERSITY 



BULIMULUS-CENTRAL AMERICAN. 57 



wrinkles and an appearance of very faint spiral stria3 below the 

 sutures, which are but little impressed and under a lens seem to be 

 very narrowly margined by transparence. Spire rather straightly 

 conic, the apex obtuse, nepionic whorls with shallow, fine, short- 

 waved interrupted and dislocated wrinkles, and slight, fine, im- 

 pressed spiral striae. Whorls 6*, weakly convex, the last obsoletely 

 angular at the periphery. 



Aperture rather narrowly ovate, brownish-corneous inside, deci- 

 dedly less than half the length of the shell ; peristome thin and 

 unexpanded ; columella slightly concave, the columellar margin 

 dilated and reflexed above. 



Alt. 27, diam. 12J; alt. of aperture 12| mill. 



Alt. 23 J, diam. 10 ; alt. of aperture 9f mill. 



Alt. 20, diam. 9 ; alt. of aperture 9 mill. (type). 



Alt. 25, diam. 11 ; alt. of aperture 101 mill. 



Honduras (Dyson) ; Nicaragua (Swift. Coll.) ; around Duenas t 

 Guatemala (Salvin) ; Yucatan (Martens). 



Bulimus dysoni PFR., P. Z. S., 1846, p. 39 ; Monogr., ii, p. 183. 

 REEVE, Conch. Icon., pi. 62, f. 425. Buliinulus dysoni CROSSE & 

 FISCHER, Moll. Terr, et Fluv. Mex., p. 551. MARTENS, Biol. Amer. 

 Centr., p. 241. 



The columella may be faintly seen through the shell in clean 

 examples, as Reeve has already remarked. The spire is rather 

 straight, whorls but little convex, and the last one is obsoletely 

 angled, the angle most visible ventrally, where it arises exactly at 

 the upper insertion of the outer lip. The appearance of spiral 

 striation is like that of B. cacticolus, and depends on some structural 

 character of the shell-substance rather than on an actual sculpturing 

 of the surface. There is a considerable range of variation in the 

 length of spire, as usual in Bulimulus, some specimens, like that last 

 measured above, having it quite long. The apical sculpture is like 

 that of cacticolus. 



A tray of 8 specimens from Cuidad Bolivar, Venezuela, shows no 

 material variation from the Central American shells. They are 

 slightly more opaque and of a trifle redder tint. The locality datum 

 can hardly be questioned, as the original label accompanies the 

 shells. 



Var. IGNAVUS Reeve. PI. 10, fig. 86. 



Shell oblong-ovate, rather deeply umbilicated, whorls 7, rounded, 

 longitudinally very finely striated ; columella broad, slightly re- 



