66 VARICELLA. 



downwards. Length 12, diam. 2.66, aperture 3.33 x 1.33 mm. 

 (Pfr.). 



Jamaica (Ph. Gosse in Chiming 'coll.). 



Achatina gossei PFR., P. Z. S. 1845, p. 138; Monogr. ii, 

 267. REEVE, Conch. Icon, v, pi. 20, f. 114. 



Reeve's figure is copied. I have not identified this species. 

 It is smaller than V. chittyana with the same number of 

 whorls, and it seems to tie more remotely ribbed than that 

 species. Pfeiffer's description is not sufficiently explicit con- 

 cerning the details of sculpture. 



13. V. COSTULATA (C. B. Adams). PI. 13, figs. 10, 11, 12. 



Shell small, conic, thin, diaphanous, brownish, with two 

 black-brown bands; suture deep. Whorls 8, sufbangular 

 above, furnished with very slender close riblets. Lip thin, 

 retracted below. Columella not very much arched. Diver- 

 gence 20 degrees. Length of spire .23; total length .335, 

 width .1 inch. [8.37 x 2.5 mm.]. (C. B. Ad.). 



Jamaica : 



Achatina costulata C. B. AD., Proc. Bost. Soc. Nat. Hist, 

 ii, 1845, p. 13. REEVE, Conch. Icon, v, pi. 20, f. 112 (March, 

 1850). PFR., Monogr. ii, 267; iii, 497; iv, 610; vi, 231. 

 Achatina adamsii PFR., P. Z. S. 1845, p. 138. 



Figs. 10-12 represent a specimen received from Adams. 

 It measures, length 7.5, diam. 2.3 mm., whorls 7!/2- The first 

 2y 2 form a pupiform embryonic shell, which is about .9 mm. 

 in diameter at the last whorl. The initial half whorl is 

 smooth; then radial riblets set in, are rather coarse at first 

 but become closer on the last embryonic whorl. They are 

 nearly or about as wide as the intervals, are rounded and 

 smooth-, the intervals are also smooth. The post-nepionic 

 whorls are all convex, the last somewhat less so but not flat- 

 tened. Sculpture is of regular, narrow and delicate vertical 

 riblets, reaching from suture to suture on the spire. On the 

 last whorl they disappear at the base, and number about 

 28. The intervals have 8 or 9 parallel striae, with no spiral 

 cords or striae. The varices are very low and inconspicuous. 

 The shell is corneous with curved, longitudinal chestnut 



