SPIEAXIS. 31 



specifically. The name proposed by Adams was preoccupied, 

 and hence the form was re-named by Pfeiffer. 



Some s'hells are more slender than Adams' type. One be- 

 fore me, fig. 10, measures 5.8 x 1.5 mm., with 7% whorls. The 

 strise are shown somewhat too strongly in figs. 8 and 10. 



33. S. MACROSPIRA (C. B. Adams). 



"Shell much elongated, conic; pale horn color, or brown- 

 ish, with a few scattering stripes of dark brown : shining, 

 with excessively minute distant striae : spire with the outlines 

 a little 'concave above, otherwise slightly 'Curvilinear : apex 

 obtuse, rather small : whorls twelve, a little convex ; with a 

 well impressed suture; last whorl short: aperture ovate, 

 rather wide : lab rum thin and sharp : columella nearly 

 straight. Mean divergence about 18 ; length .8 inch ; breadth 

 .22 inch; length of aperture .2 inch." (Adams). 



Jamaica: Maroontown, St.. James (Chitty). 



Biilimus mocrospira C. B. A., Contrib. to Conch, no. 9, 

 p. 169 (April, 1851). PFR., Monogr. iii, p. 399. B. macro- 

 spirus Ad., PFR., Monogr. iv, p. 457 (new description). 



The type of this species is probably in the Chitty collection 

 in the British museum. It is not in that of Adams at Am- 

 herst. Its exact systematic position is uncertain. Dr. 

 Pfeiffer, in his later reference to the species, described a 

 specimen in the British Museum from Maroon Town, St. 

 James, probably given by Chitty, and somewhat smaller than 

 the type, length 17, diam. 5, aperture 4.5 mm.., with 9 to 10 

 whorls. 



Subgenus SIGMATAXIS Pilsbry, nov. 



Glossy, translucent, pale shells, often with distant varix- 

 stripes, the surface sculptured with longitudinal grooves. 

 Aperture long-ovate or piriform; outer lip simple, arched 

 forward; columella concave below, ascending in a moderate 

 or gentle spiral. Type S. Iceviusculus Ad. 



A Jamaican group of small forms, distinguished from 

 Volutaxis by the longer whorls, long aperture, and smooth, 

 grooved but never ribbed or thread-striate surface. 



I have examined the type specimens of nine of the thirteen 



