PROSOBRANCHIATA. 285 
hollow space between the suture and the shoulder is traversed by several irregular, 
shallow, almost obsolete furrows. The body whorl is much contracted in front, whence 
it tapers gradually to the base, forming a long, wide, and nearly straight canal: four or 
five concentric lines cross the middle of the last whorl; these lines are rounded, 
rather distant, and separated by wide concave spaces ; over the front of the whorl, 
and as they descend the canal, the concentric lines become gradually closer and less 
prominent, and at last are almost obsolete on the anterior extremity of the canal. 
The aperture is of an oblong-oval form; the outer lip arched, somewhat wing-shaped, 
projecting slightly towards the posterior extremity; and the sinus, which is placed 
on the shoulder, is rather wide, very deep, and triangular. 
In the series forming part of Mr. Wetherell’s collection, two or three specimens 
occur in which the line of the suture being less decurrent, the margins of the whorls 
extend quite up to the shoulders; the shell, consequently, is a little wider, and the 
spire not so much elevated; but this difference appears to be accidental and scarcely 
constitutes a variety. 
Size.—Axis, 1 inch and 1-8th; diameter, not quite 4-12ths of an inch. 
Localities. —Highgate Archway, Cuffell. 
No. 211. Pxieuroroma WetHerectu. VF. &. Edwards. Tab. XXIX, fig. 16, a—d. 
P. testa elongato-fusiformi, costellatd, undique spiraliter lineata: spird mediocriter 
elatd, sub-conicd : anfractibus sub-angulatis, suturd perspicud separatis, antice convewius- 
culis ; marginibus posticis latis, sub-rectis ; costellis numerosis, curvis ; lineis spiralibus 
medianis distantibus, crassis, pre-eminentibus ; ceteris filliformibus, crebrioribus : apertura 
oblongo-ovali, in canali longo ewxeunti ; labro arcuato; sinu lato, profundo, ad humerum 
collocato. 
Shell elongated, fusiform, ribbed and concentrically lined ; the spire moderately 
elevated, rather thick, and nearly conical: the whorls, seven or eight, bluntly angu- 
lated at the shoulders, and slightly convex in front ; the poséerior margins wide and 
nearly straight. The ribs vary much in size, being more or less lengthened in the 
direction of the axis in different individuals; the concentric lines over the middle of 
the whorls are more or less distant, thick, and very prominent; over the shoulders 
and posterior margins they are finer, thread-like, more closely set, and irregular. The 
aperture is oblong-oval in shape, and terminates in front in a long, wide, and slightly 
oblique canal; the outer lip is much arched, thin and sharp on the edge, and 
smooth within; and the sinus is moderately wide, deep, sub-trigonal, and placed 
on the shoulder. 
A variety occurs in which the posterior margins of the whorls are narrower, and 
the sutural edges slightly thickened. 
