SCYLLJSA.
3. Interior of the buccal mass, exposed from above:—a, channel of the mouth; b, b, cutting
edges of the corneous jaw ; c, c, portions of the jaw exhibited on the surface ; d, oesophagus;
e, tongue covered with rows of spines.
4. External view of one of the corneous jaws :—a, cutting edge.
5. The stomach laid open with two of the liver masses attached :—a, interior of the stomach; b,
belt of homy plates lining the same; c, oesophagus; d, intestine; e, e, hver balls, showing
the tubes branching over their surface; ƒ,ƒ, ducts leading from the hver balls to the stomach;
g, g, two of the canals resulting from the union of the tubes that branch over the hver masses
and go to the skin.
6 Two of the homy plates from the belt lining the stomach.
7 One of the liver balls bisected longitudinally, exhibiting the internal stru c tu r e a, central
duct leading to the stomach; b, minute ramifications of the same leading to c, the tubes
composing the inner layer; d, outer layer of small canaliculated tubes.
Fam. 3.
{The Figures are included in PI. 5 of Fam. 2.)
Genus 10. EUMENIS,* Alder and Hancock.
Corpus elongatum, quadrilaterum. Caput sub-inferius, velo parvo obtectum; maxillis comeis.
Tentacula duo, dorsalia, clavata, et laminata, intra vaginas retractilia. Branchiae sub-papillosae, mem-
brano undulato, ad latera dorsi utrinque longitudinaliter extenso. Pes linearis. Orificia generationis
et ani ad latus dextrum.
This genus was formed by us for the reception of a curious animal found in Torbay ; and
was published in the £ Annals of Natural History) for November, 1845. Since then we have
met with another species in Lamlash Bay, Isle of Arran, agreeing in all essential particulars
with the characters on which we had founded the genus, and consequently strengthening our
opinion that those characters are generic. In external form this genus very much resembles
Tritonia, but it differs from it in the papillose character of the branchiae; in which respect,
as well as in its internal structure, it shows a much nearer alliance to the Eolidida, amongst
which we have placed it. It constitutes, however, an intermediate form uniting the two
families.
The body of Eumenis is elongated and quadrilateral, truncated in front, and ending in
an obtuse point behind. The head is sub-inferior, with corneous jaws, and is covered by a
small tuberculated v eil; there are two tentacles, which are dorsal, clavated, and laminated,
and are retractile within small, plain, or tuberculated sheaths. The branchiae are sub-papillose,
and arise from a waved membrane set along each side of the back, forming a continuous base
from which the papillae arise into obtuse points. The sides of the body are vertical. The
foot is linear, but not very narrow, deeply cleft and arched in front, and extending into long
tentacular processes at the sides. The orifice of the generative organs, and the anus are on
the right side.
In consequence of our observations having been confined to a single individual in an
imperfect state of preservation, the anatomy of this genus has not been very fully made out.
The buccal mass resembles very much that of Folis, but is larger in proportion to the
size of the animal, and the muscles, though arranged in the same manner, are more powerful.
The corneous jaws differ only in being flatter and shorter. The tongue is placed in the centre
of the mouth on a wedge-shaped muscle, and is composed of about fifteen transverse rows of
stout, well arched teeth or spines, minutely denticulated on each side, and having their points
* Eumenis, a fury. Since the institution of this genus, we have found, in the volume of ‘Reports
oh Zoology/ lately published by the Ray Society, the description of a genus of M. Verany under the
name of Lomanotus, which appears to be similar to, if not identical with ours. We regret that our
not having had the opportunity of seeing the periodical in which this genus was published, prevented
our adopting it. Should it prove the same as ours, we believe M. Verany’s name will have the
precedence.