is somewhat bluntly rounded. The remarkable feature about it. however, is the presence
of a broad web or lamina attached to its lower surface, and which tapers from base to
tip. The organ, therefore, forms an efficient rudder. The body is delicate and brittle,
and the length of the bristles still further adds to the characteristic appearance.
Scales (Plate XXXIII, fig. 1), fifteen pairs, thin but tough, entirely covering the
back, comparatively large and apparently smooth to the naked eye, but minutely granular
under a lens. The first pair are rounded, the succeeding more or less ovate, and all with
a smooth border. The entire surface is studded with minute horny spines, which increase
in size from the inner to the outer border, and especially posteriorly. No part of the
scale is free from them. I t sometimes happens that a few of the larger conical spines
project beyond the posterior border under examination, but otherwise the edge is smooth.
In shape almost all the spines are acutely conical. The scales are pale, and the scar for
the pedicle has an unusually large area behind it, from the great development of the
posterior region. The scales, as a rule, adhere firmly. In a mounted scale a number of
rounded bodies of various sizes, with a distinct capsule and granular contents, occurred,
along with certain rectangular bodies composed of two halves, like Desmids. Their
nature is enigmatical.
Feet.—The first bears a short, slightly curved bristle or two of the dorsal pattern,
and resembling the shorter forms next the body in the typical foot.
The second foot presents a double ellipse—one for each division—with the projecting
papilla for the spine, the inferior having in addition a fleshy digit-like process
above the spine. A few of the inner bristles of the dorsal tuft are-short and curved like
those of the tentacular cirrus, each, however, having a smoothly pointed tip. The chief
bristles are long, translucent, and tapering, with a long bare tip marked by wide and
slightly oblique spinous rows, so that in some views it resembles an Equisetum of glass.
The ventral bristles are slender and elongate, with long spinous regions tapering to a
delicate tip, which is bare, and provided with a terminal hook. The filiform tip of the
long ventral cirrus extends beyond the bristles.
The next foot leads to the typical shape, which is peculiar, since in a ventral view
the tip is rounded. In profile, again (Plate XXX, fig. 10), the outline of the ventral
division is comparatively deep and rounded, with the spine near the middle, and the bristles
project as a broad fan. Dorsally the bristles (Plate XL, fig. 1) are remarkable for their great
length, diaphanous nature, and brittleness—conditions pointing to a pelagic habit. The
dorsal lobe itself forms only a small boss or eminence, and is thus in marked contrast
with the same region in Evarne impar. From the inner side of this eminence spring
a few short, slightly curved tapering bristles, with closer rows of spikes, next which
are some shorter straight ones (Plate XL, fig. 3). The rest are large straight bristles
(Plate XL, fig. 2), tapering almost from the base to the smooth and sharp tip. The
spinous rows are short, slightly oblique, and very wide, as in an Equisetum, the appearance
of the whole being diagnostic. The ventral series consist of elongated and slender
bristles (Plate XL, fig. 4), with long and finely tapered spinous regions superiorly. They
terminate in a long smooth tip, which is bifid and slightly hooked. The bifid condition,
however, is difficult to detect in some, and inferiorly the tips are simple. The bristles
can be followed in the diaphanous foot inwards to the muscular boss at the spine.
Posteriorly the dorsal eminence disappears, and the bristles become more slender,
but still retain their characteristic structure. The tips of the slender ventral series are
extremely elongate, but traces of the bifid condition are still to be found in many. The
foot is thus practically formed of the ventral lobe.
In young examples the bristles, especially the ventral, are proportionally longer,
and at this stage—5 to 6 mm.—two were pelagic at the surface.
In the development of these bristles the tip is practically complete oh issuing from
the foot, and additions are made posteriorly as it pushes out.
The dorsal cirri have the form of the tentacular cirri, and their filiform tips extend
beyond the bristles. The ventral cirri are slightly brownish (madder), elongate,
subulate organs, the slender tips of which extend beyond the fleshy part of the foot.
They are perfectly smooth.
The delicacy of the body, the structure of the feet and bristles, as well as the
rudder-like caudal style, show that this species has peculiar habits, probably more or
less pelagic. What relation it may hold to other forms is unknown, and epigamy, or the
epitocous condition, may yet be clearly demonstrated in the family.
4. Evarne atlantlca, McIntosh, 1897.
" Specific Characters.—Head like that of Evarne impcur, but the cilia on the tentacles
and the papillae on the palpi seem to be smaller. The cirri generally are more slender.
Dorsal bristles longer and less curved than in E. impar, and their rows of spines closer.
Ventral bristles have longer tips than in E. impar.
S ynonym.
1897. Evarne atlantica, McIntosh. Ann. Nat. Hist., ser. 6, xx, p. 168.
Habitat.—Dredged at Rockall (Station 3a) by the Royal Irish Academy’s Expedition,
June 15th, 1896.
A fragment of about fifteen segments of the anterior end.
The head resembles that of E. impcvr, Johnst., in general outline, but differs in
having somewhat smaller eyes. The tentacles and palpi also are similar, though the
cilia on the former and the minute papilhe on the latter are less bold. The cirri
generally are a little more slender.
The body is thicker and more massive than in E. impar of the same size, and both
dorsally and ventrally in the preparation has a pinkish skin-colour. The arrangement of
the bristles at the side of the body is more trim. No segmental papilla is observable,
though the eminence is distinct. In this respect it agrees with E. impar of the same
size, in which the papilla only becomes noticeable about the twelfth bristled foot. In
large examples it is evident on the seventh bristled foot.
J |j||;—The first foot (bearing the tentacular cirri) has a few short bristles conforming
to the dorsal type, though with somewhat closer rows of spines. In the second foot the
dorsal bristles are longer and less curved than in E. impar, and while there may be room
for doubt concerning the proportionate distances of the spinous rows, there can be none