286 PROCEEDINGS OF THE ACADEMY OF [Sept., 



Boltenella exoellans n. sp. PL XVIII, figs. 3, 4. 



Description. — Shell of medium size and thin; elevation of the spire 

 less than the length of the aperture; whorls closely appressed and 

 strongly shouldered by a broad concave shelf, whorls five in number, 

 increasing in size from a minute apical whorl to a much inflated body; 

 protoconch fairly large and bulbous; smooth and naticoid, coiled 

 two and a half times; sculpture well defined but somewhat subdued; 

 axials elevated and low, well rounded and short, persisting on the 

 whorls of the spire to the anterior suture but evanescing a little in 

 front of the shoulder angle of the body, axial ribs nodulated on the 

 body, nodes occurring directly upon the shoulder angle while the 

 axials persist for a short distance across the shoulder; spiral sculpture 

 low and fine, slightly irregular with secondary spirals developed in the 

 interspiral depressions near the aperture; spirals microscopically 

 roughened by the intersection of numerous incremental lines; suture 

 appressed and undulated by the axial ribs of the preceding whorl; 

 body much inflated, shouldered behind, rounded or globose in front, 

 and merging into a long straight pillar which may be straight or 

 curved; aperture broadly ovate, grooved at the posterior commissure 

 and produced in front into a narrow canal; outer lip thin and simple; 

 inner lip excavated at the base of the body; columella smooth, 

 reinforced at the entrance of the anterior canal by a deposit of callus; 

 parietal wall thinly glazed, outer margin of the wash sharply defined. 



Dimensions. — Altitude 38.4 mm.; elevation of spire 13.5 mm.; 

 maximum diameter 18.7 mm. 



This species is represented in the Coon Creek collection by several 

 well preserved specimens, a few of which show the protoconch. 

 The species is characterized by fulguroid shells which are ornamented 

 on the external surface both by axial and spiral sculpture. They 

 have a broad, slightly concave shoulder and the angle of the shoulder 

 is nodulated on the body by the axial elevations. 



Genus SCOBINA n. gen. 



Etymology: Scohina, a file or rasp, name applied because of the 

 rasp-like character of the incremental serrations along the anterior 

 carina of the type species. 



Type: Scohina hicarinata n. sp. 



Shell moderately large and strong, top-shaped in outline; spire 

 acute at the apex, its elevation less than half the total altitude of the 

 shell; protoconch scar small; whorls closely appressed, obliquely 

 shouldered, whorls of spire unicarinate, body flattened along the 



