S ynonym.
1876. JEusthenelais hibenvica, n. g. and s., McIntosh. Trans. Zool. Soc., vol. ix, p. 407, pi. Ixxiii, ff. 4 and 5.
jHabitat.—Dredged in the ‘ Porcupine ’ Expedition of 1869 at Station 8, off the
west coast of Ireland (Galway) in 106 fathoms, and again in the Expedition of 1870 off
Cape Sagres in the Mediterranean, in 45 fathoms.
Head (Plate XXIX, fig. 5) as in Sthenelais Jeffreysii, broadly ovate, with a median
region and two well-marked ovoid lobes at the sides. Eyeless in the preparations. The
median tentacle is similar to that of the species mentioned, and has a filiform tip. At its
base are two small processes (ctenidia), which do not reach to the tip of the basal
segment. The appendages springing from the first foot agree with those of Sth.
Jeffreysii. The external process, corresponding to the dorsal cirrus, is slightly shorter
than the median tentacle, and has a filiform tip. The shorter and more slender lateral
tentacle lies to the inner border dorsally. Beneath are two processes,—an inner, short,
broad, and blunt (cuilleron), with the flattened tip extending beyond the peduncle ; and
an outer, slender, tapering, ventral cirrus, which is not half the length of the dorsal.
The palpi are long, smooth, and tapering, with a scoop-shaped lamella at the base
superiorly and internally.
Body probably about two inches in length, and having numerous segments. I t is
rounded dorsally and flattened ventrally.
Scales absent. In all probability the scales will be found to present long papillæ on
their external border—if we may judge from its close resemblance to Sthenelais Jeffreysii
and its Norwegian ally, as well as to Sth. fuliginosa, Claparède.1
Feet.—The second foot bears a scale and a long ventral cirrus, and the third a
dorsal cirrus of considerable length, while the fourth has a branchial process arising
from the homologous base. The bristles in the second foot have already mapped themselves
out more or less as they occur behind, though of course less distinctly. The
branchia is short anteriorly, but gradually increases in length till about the middle of the
body. A single large ciliated pad (ctenidium) exists on the dorsal edge of the foot, and
three smaller in the curve below the cirrus. In the typical foot (Plate XXXI, fig. 9) the
dorsal lobe is somewhat clavate, and bevelled at the tip superiorly. I t bears three or
four long papillæ. The dorsal bristles are slender, elongate, and tapered to a fine hairlike
point. All are finely spinous, one series more distinctly, and another less distinctly
so. The ventral lobe is conical at the tip, has a rounded lobule in front, bearing
a very long papilla, which extends beyond the tip of the dorsal lobe. At the spine is
another somewhat fusiform papilla, and on the inferior lobule a longer and more slender
one. The superior ventral bristles have rather slender shafts, and the distal ends are
furnished with from seven to nine whorls of spikes. The distal region is a slender
tapering process of from fifteen to eighteen joints, ending in a capillary tip. These
resemble the bristles of Sthenelais and Sigalion rather than those of Leanira, since the
necklace-like canaliculi are absent. The figure (Plate XLII, fig. 9) represents a bristle
adjoining the superior lobe, the spinous rows on the tip of the shaft being more numerous,
while the jointed terminal region is shorter.
1 * Ann. Chæt. Nap./ p. 94, pi. iv, fig. 2.
At and below the spine are a series of bristles having stouter shafts, without spines at
the distal ends, and bearing shorter divisions to the terminal whip. The slender group at
the ventral border of the foot, that is below the inferior lobule, have in some cases one
or two spines at the end of the shaft, and long tapering and numerously (fifteen to
sixteen) jointed terminal regions, with a minute claw and secondary process at the tip
(Plate XLII, fig. 10). These bristles also lean to the two forms mentioned, and not to
Leani/ra.
The ventral cirrus is long and subulate, reaching almost to the tip of the fleshy part
of the foot. I t has an articulation at the extremity.
Habits.—This species would seem to frequent sand in deep water, but it may yet be
found inshore.
I t is closely allied to Clapar^de’s Sthenelais fuliginosa.
Genus XXVI.—Sigalion, Audouin and M. Edwards, 1830.
Head elongate from before backwards. Median tentacle absent ; lateral tentacles
short and papilliform, fixed to the anterior part of the cephalic lobe. Scales covering
the dorsum; processes pinnate or with long papillse from the axis. The feet resemble
those of Sthenelais. Dorsal division clavate and furnished with a papilla. Bristles as
in Sthenelais. Ventral division somewhat truncate, and with a papilla internal to the
bristles, which are all bifid. Branchiae on every foot1 (in S. Mathildas). Nerve-trunks
rounded in section, and the granular epidermic area enclosing them is expanded
inferiorly. Segmental eminence placed ventrally at the base of each foot.
1. Sigalion Mathilda, Audouin and M. Edwards, 1834.
Specific Characters.—Head elongate from before backward, with a truncate anterior
border, having a slight peak at each side. Behind the border are two pairs of
small black eyes, the anterior nearer each other and larger. Body elongate (three
to five inches), little tapered anteriorly, and gradually diminishing posteriorly.
Segmental eminence situated ventrally at the base of each foot. Colour greyish-
brown or pinkish; Proboscis with seventeen to eighteen papillse on each lip.
Scales about sixty-four pairs, adherent, somewhat quadrate or rhomboidal, with
the posterior and inner corner rounded off. The processes along the external
border are pinnate, with long cylindrical papillaa (about twenty on each side),
and at the base these are irregularly distributed around the central axis. Poot
with a club-shaped dorsal division, which has a single subulate papilla, and simple,
tapering, finely spinous bristles—increasing in strength externally. The inferior
1 Carus, in his ‘ Prod. Fauna Medit./ states that in the anterior part of the body the branchiae
alternate with the elytra, but that posteriorly they occur on all the feet.