A... Verrill—Mollusca of the New England Coast. 165 
also resembles Spirotropis ephamilla, but the latter has a deeper 
notch, more remote from the suture, its subsutural band is broader, 
and the shoulder of the whorls less marked, while the canal is longer 
and more constricted at its base. 
RACHIGLOSSA. 
Marginella borealis Verrill, sp. nov. 
Marginella carnea Verrill, Catal. Mar. Moll., Trans. Conn. Acad., v, p. 489, (non 
Storer.) 
PuatE XXIX, FIGURE 4. 
Shell of medium size, solid, smooth, somewhat shining, with a 
rather elevated, acute spire, showing all the whorls, of which there 
are about five. Last whorl somewhat swollen, with a slightly prom- 
inent, rounded shoulder, considerably below the suture. 
The whorls of the spire increase regularly in size and are slightly 
convex ; the nuclear whorls are smooth, polished, shining, evenly 
rounded. Suture distinct, though filled up with the thin coating of 
enamel that covers the spire, but does not conceal its structure. The 
aperture is narrow, expanding a little anteriorly, towards the canal, 
which is evenly rounded at the tip. The outer lip is thickened by a 
stout rib, evenly ronnded externally, and faintly crenulated on the 
inner margin, especially on the anterior half. The posterior sinus is 
distinctly marked as a smooth, rounded groove, surrounded by callus, 
at the junction of the lip with the body-whorl. The inner lip has a 
conspicuous, raised, ovate patch of white callus along the posterior 
half, covering the adjacent portion of the body-whorl, and extending 
backward more or less on the spire; on the anterior half there are 
four oblique, stout, prominent plications, nearly equal in height ; the 
most anterior of these is formed by the twisted inner edge of the 
columella, forming the inner border of the canal; the most posterior 
is less oblique and often a little smaller than the others. The callus 
extends along the lower lip, outside of the plications, to the anterior 
border of the canal, sometimes, when best developed, forming by its 
outer margin a slight groove. Shell yellowish flesh-color, varied with 
whitish ; sutural lines, callus deposits; plications, and inner margin 
of the outer lip, white; external surface of the thickened outer lip 
usually with three orange-yellow spots, the largest of which forms a 
narrow, elongated patch along the anterior and outer border of the 
canal, extending somewhat backward along the lip; the next is usually 
a broader, oblong patch, just below the shoulder ; the third is a 
small, rounded spot close to the suture. Frequently the anterior 
