STROPHOCHEILUS-BORUS. 13 



S. POPELAIRIANUS Nyst. JP1. 1, fig. 1 ; pi. 2, fig. 1 ; pi. 3, fig. 10. 



Shell very large, solid, rimate, ovate-conic ; spire subregularly 

 tapering, the penultimate whorl somewhat bulging, last whorl de- 

 pressed on the back. Dark reddish-brown or rich chestnut with nar- 

 row darker streaks and a lighter margin below the suture ; the 

 earlier whorls dull reddish, apex wbite. Surface covered with a 

 strong cuticle, shining. Xepionic shell distinctly marked, with 4 

 whorls, sculptured with strong narrow radial riblets, which on fourth 

 whorl become obsolete toward suture below. Succeeding whorls 2, 

 having growth-wrinkles and a dense but rather irregular spiral 

 granulation which fades out upon last whorl, which is more coarsely 

 sculptured by lengthwise wrinkles and has generally more or less- 

 coarse spiral malleation. Sutures deep, the last decidedly more 

 oblique. 



Aperture about half the shell's length, trapezoidal, white with a 

 livid tint within. Outer lip well reflexed, white (or light-brown 

 edged), convexly curved ; columella white, reflexed, and in the im- 

 mediate vicinity of its insertion spreading upon the whorl and con- 

 tinued in a strong white callus across the parietal wall. Near the 

 upper termination of parietal callus there are usually one or two low 

 callous nodules. 



Alt. 136, diam. 85 mill, (specimen). Nyst's figure measures 155 

 x 98 mill. 



Quito (Isern), Bodega (Paz), and Napo (Martinez), Equador ; 

 Bolivia (Castelnau, doubtful). 



Bidimus popelairiana NYST, Bull. Acad. Roy. de Bruxelles, xii, 

 (2), p. 151, pi. 3, f. 5 (1845). Bidimus popelairianus PFR., Mono- 

 graphia ii, p. 20. HIDALGO Mol. Viaje al Pacif. p. 46, pi. 3, f. 7. 

 MARTENS, Novit. Conch, v, p. 3, pi. 139, f. 1, 2 ; pi. 140, f. 1, (with 

 varieties). Bulimus maximus HUPE in Castelnau's Anim. nouv. ou 

 rares rec. dans TAmer. du Sud, Moll., p. 24, pi. 4, f. 1. 



The generally larger size, more bulging penultimate whorl, broader 

 contour and larger aperture seem to be the chief differences between 

 this species and S. maximus Sowb. 



A young specimen of var. thammianus measures at time of extru- 

 sion from egg (marked by a broad brown stripe in this species) 41 

 mill. long. It is finely granulated as well as ribbed. First whorl 

 nearly planorboid, smooth ; last whorl ribbed only above. Whorls 4. 



