VARICELLA, PORTO RICO, ST. THOMAS. 121 



This little species 'has about the proportions of V. "biplicata, 

 but differs conspicuously from that in its sculpture of 

 widely spaced grooves, in place of the close, hair-like striae 

 which give a silky luster to biplicata. There is, moreover, 

 no trace of a spiral fold upon the columella. 



A dead specimen in the same lot is somewhat larger, 11.4 x 

 3 mm., aperture 3.3 mm., with 714 whorls. The last two 

 whorls are rather conspicuously flattened. 



Form from St. Thomas, pi. 18, fig. 32. Dead shells which 

 have lost color, and may not be full grown are before me. 

 The shell is sculptured with unequal, unevenly spaced 

 grooves after the first two smooth whorls. The aperture is 

 pirif orm ; the columella. is very deeply concave, abruptly 

 truncate at the base. A small false umbilicus is seen in 

 basal view, as in V. elata. Length 6.8, diam. 2, length of 

 aperture 2.3 mm. ; whorls 5%. 



St. Thomas: Freydendal, and a hill opposite Baker's 

 (T. Bland). 



Achatina - f Sp. undet., BLAND in Adams' Contribu- 



tions to Conchology no. 11, 1852, p. 219, no. 8 (22) ; no de- 

 scription. " Achatina siibtilis Shuttl.," label in R. Swift 

 collection. 



This form differs from V. elata by its rather sparse, irre- 

 gularly spaced grooves. It has a more concave columella 

 than Pfeiffer figures for his V. impressa, and the columella 

 is perhaps perceptibly more gyrate than in the larger tere- 

 brceformis. I have not been able to trace the name A. subtilis 

 Shuttl. to a description. 



68. V. SULCULOSA ( S'huttleworth) . PI. 19, fig. 35. 



Shell turrite-subulate, thin, very smooth, 'Closely marked 

 with rather deep impressed lines, very glossy, pale corneous, 

 ornamented with reddish streaks here and there. Spire long, 

 the apex obtuse. Whorls 7, a little convex, the last nearly 

 one-third the total length; suture nearly simple. Aperture 

 semioval; peristome simple, acute, the right margin notice- 

 ably arcuate ; 'columella strongly arcuate, base truncated. 

 Length 10, diam. 2.66, aperture 3x2 mm. (Shuttlew.) . 



