go Bulletin 29 254 



Metulella Williamgabbi, n. sp. 

 Plate 15, Figure 29 



Shell slenderly fusiform, whorls nine, the first two smooth, 

 nuclear, subsequent volutions ornamented by uniform, narrow, 

 longitudinal riblets of which there are twenty-five on the last 

 whorl; spiral striae faint, obsolescent; whorls flattened on the 

 sides; narrowly channelled above the suture; aperture elliptical ; 

 inner lip with a callus bearing six transverse denticles; outer lip 

 with six distinct lirae and a seventh weaker one within the 

 aperture. Length of shell 17, of aperture 7, of spire 10; greatest 

 width 6 mm. 



This species is very closely related to M. fusiformis, but can 

 be easily differentiated by its laterally flattened whorls, higher 

 spire, and obsolescent spirals. The surface is not regularly can- 

 cellate, nor are the whorls evenly and convexly rounded as in 

 M. fusiformis. 



This interesting shell is named in honor of Professor Gabb 

 by whom it was collected in Santo Domingo over forty years 

 ago. It is the third species of his Dominican genus Metulella. 



Genus Alectrion Montfort 



Alectrion cercadensis, n. sp. 



Plate 15, Figures 19, 20 



Shell small, acute, with two and a half nuclear, and four and 

 a half post-nuclear whorls; longitudinal sculpture of small, 

 rounded, oblique ribs, twelve on the last whorl; the ribs often 

 become obsolete on the body whorl, spiral sculpture of raised 

 threads, nodular on crossing the ribs, four to six on each volu- 

 tion of the spire; on the bod}'' below the four spirals is an anter- 

 ior set of ten finer spirals; where the ribs become fainter, equal- 

 ling the spirals, a subcancellate ornamentation results, very char- 

 acteristic of this species; anterior sulcus deep; beak sculptured 

 by six spirals; outer lip with a stout external varix, denticulate 

 within and with long lirse. Length 7.5, greatest width 5.25 mm. 

 A cancellate specimen with obsolete ribs on the last whorl meas- 



