418 A, E. Verrill—Mollusca of the New England Coast. 
half, of which three belong to the nucleus, which is rather large, 
regularly coiled, the apical whorl rather small, a little depressed, 
white and polished; the second whorl is also polished, but crossed by 
very fine lines of growth; the last nuclear whorl has about five 
raised, revolving cinguli in addition to the lines of growth. 
The lower whorls are crossed by numerous rather straight, obtuse 
ribs, separated by intervals of about their own breadth; of these 
there are about twenty-four on the last whorl. Each of these ribs 
rises into a rounded, rather prominent tubercle at the shoulder; they 
are faintly marked and oblique on the concave subsutural band, but 
form another circle of obtuse tubercles just below the suture; an- 
teriorly they fade out at about the middle of the body-whorl. The 
suture itself is impressed and undulated. The surface, both of the 
ribs and intervals, is covered by close but distinct lines of growth. 
At the shoulder a distinct revolving carina connects the tubercles 
together; below this there are pretty regular, well-developed revoly- 
ing cinguli, which are rounded and separated by rather wide inter- 
vals, and cross both ribs and interspaces, but in crossing the ribs they 
become more prominent and form oblong nodules on the upper part 
of the whorl; on the lower part of the whorl and siphon they are a 
little wider, more spaced, and roughened only by the raised lines of 
growth. On the penultimate whorl there are three or four revolving 
cinguli below the carina. The subsutural band is strongly marked, 
broad and decidedly concave, and is covered with slightly curved, 
oblique lines of growth and faint ribs, and has a single, small, revolv- 
ing cingulus in the middle. The aperture is long, ovate-fusiform, 
angulated at the outer lip, and with an acute posterior angle; an- 
teriorly it is narrowed into the moderately long straight canal; the 
posterior sinus is nearly obsolete. Columella straight, with a sinuous 
inner margin. Operculum greenish yellow, ovate, obtusely rounded 
posteriorly, subspiral anteriorly, with the nucleus near the inner 
anterior edge. Epidermis pale yellow, thin, closely adherent. Color 
of the shell within, bluish white; nucleus white. 
Length, 16™"; breadth, 8"; length of body-whorl in front, 7"™; 
length of aperture, 5"; its breadth, 3°5™™; length of operculum, 
4°5™™ > its breadth, 3™™. 
A single living specimen (No. 44,655), was taken at station 2,226, 
in 2,021 fathoms, N. lat. 37° 00’, W. long. 71° 54’. 
This fine species has some resemblance to the northern ZB. scalaris, 
but has a finer and more regular sculpture, and is easily distinguished 
by the distinct circle of nodules just below the suture, a peculiarity 
