A. JS. Yerrill — Molhisca of the JVeto England Coast. 181 



few revolving lines appear ; the lower whoi-ls are crossed hy about 

 fourteen to sixteen, regular, rather elevated, but not broad, rounded 

 ribs, which are nearly straight and separated by pretty regular inter- 

 spaces, usually about twice as broad as the ribs. On all except the 

 last whorl, the ribs extend from suture to suture ; on the last whorl 

 they fade out a little below the periphery. The whole shell, excejit 

 the nucleus, is covered with well developed, rather thin, revolving 

 cinguli, which are about the same height as the ribs, though rather 

 thinner, but in crossing the ribs they do not form nodules, so that 

 the surface is cancellated with a regular net-work, of which the 

 meshes are squarish, or elongated in the direction of the revolving 

 lines, but below the periphery of the last whorl the cinguli become 

 stronger and the ribs fainter, while the greater part of the base is 

 occupied with cinguli only, which are here rather closely crowded. 

 On the penultimate whorl there are about six or seven cinguli ; on 

 the body-whorl there are sixteen to nineteen, of which eight or nine 

 are posterior to the lip, and six or seven anterior to it. The surface 

 is also marked with very fine revolving stri®, visible under the 

 microscope. Umbilicus none. Aperture rounded or very broadly 

 ovate, usually "slightly narrowed and obtusely angled posteriorly ; 

 broadly rounded and slightly flaring in front ; outer lip sometimes 

 thin and sharp, sometimes distinctly thickened, but without a varix ; 

 anteriorly it is slightly effuse, and sometimes forms there a faint 

 rounded angle; the inner lip is continuous, forming a regular curve, 

 but not quite so convex as the outer margin ; the portion in contact 

 with the body-whorl has a free edge, and in the umbilical region the 

 margin is a little reflexed, often leaving a slight furrow beneath it. 



Length, 3"^"^; breadth, 1-6"""; length of aperture, 1-2"'^; its 

 breadth, "S"^"'. Other specimens are somewhat more slender than 

 the one measured. 



Station 2109, in 142 fathoms, off Cape Hatteras, N. lat. 35° 14' 20", 

 W. long. 74° 59' 10". Several specimens, living and dead (No. 

 35,453). 



This species belongs to the same group as C. arenaria, C. carinata^ 

 and C. areolata of our northern coasts. From all these it differs in 

 having a finer and more regular sculpture, both the ribs and revolv' 

 ing lines being much more numerous and more regular. Nor do 

 either of the northern species possess the microscopic striae. In this 

 last character it resembles C. harpa and C. leptalea; but C harpa 

 is a stouter shell, with much finer and more numerous revolving 

 lines, which do not give it a cancellated appearance. C. leptalea is 



