extremities are rare, probably because the shrimpers have removed them. Plymouth
(Spence Bate and R. Rowe) ; not uncommon between tide-marks in Guernsey and Herm ;
Dublin Bay (Southern) ; on rocky shores, as at Lochmaddy, North Uist, this species is
found under stones amongst sponges and other structures ; Firth of Forth (Leslie and
Herdman) ; Torquay (Elwes) ; abundant in the stomachs of plaice, and abundant in
St. Andrews Bay (E. M.) ; Southport (Carrington and W. C. M.) ; Shetland (tubes) (Dr.
Gwyn Jeffreys); Bournemouth, Mus. Leach (British Museum); Polperro (British
Museum) ; West Coast of Ireland, Blacksod Bay, etc. (Southern).
Abroad it extends from the Mediterranean (Delle Chiaje, Claparède, Marenzeller,
etc.) to the shores of the North Sea, the Kattegat, Scandinavia, and to Madeira
(Langerhans, Fauvel) ; New Zealand ; shores of Cantabria (Rioja) ; St. Vaast-la-Hougue
(Fauvel).
The cephalic region (Plate CXIX, fig. 8) is distinguished by its comparatively small
dorsal collar, the rim, however, expanding at each side into a great lateral flap which
in some almost meets its fellow of the opposite side in the mid-ventral line behind the
lower lip, the outline in this region thus forming a V. In others the union of the lateral
regions is more complete ventrally, some fusing so as to form a continuous band with
only a slight concavity in front, thus probably indicating the normal condition as a
continuous ventral web, the median gap being due to accidents. A marked characteristic
is the disposition of the anterior margin of the tentacular surface, for it is contracted
into a frilled spout-like border surrounding the mouth except in violent protrusion.
Within the aperture are two folds—an outer smaller, and an inner larger, tongue-like
fold. Cunningham and Ramage consider the large lower lip and the absence of eyes
characteristic of Lanice as contrasted with Terehella.
The tentacles have the usual grooved structure and form a dense mass of mobile
organs. In the centre of the living tentacle under pressure a pale band of muscular
fibres proceeds from the base to the tip. The other parts of the wall appear to consist
of an inextricable series of muscular fibres, longitudinal, transverse, or circular and
oblique. In the interior of the tentacles are numerous cells, but whether free (ccelomic)
or adherent is not evident, though they do not separate on laceration of the wall. . They
are slightly yellowish, and to some extent refract the light. When in its native habitat
the tentacles are partially protected in extrusion by entering the hollow processes of the
fringe of the tube.
The three branchiae form conspicuous and finely branched tufts on each side, the
first pair being the largest. All are sub-dichotomously divided, and the terminal divisions
are fine, so as to give the arbuscles a characteristic appearance. Moreover, they also
have a whorled aspect toward the tip. The ultimate divisions are translucent, and have
obscure longitudinal striæ with cells and granules in the wall. The first pair are situated
oh the narrow segment immediately behind the collar, a trace of which is seen in
front of the glandular ventral shield.
The long body is moderately dilated anteriorly, and gently tapered to the tail,
at the tip of which is the terminal anus surrounded by a series of marginal papillæ.
The segments are numerous, viz., from 200 to 280. The dorsum is rounded, the vèntral
surface grooved throughout, often with a central ridge, except, at the anterior shields,
which extend from the lower lip almost to the termination of the bristles. The glandular
surface is divided into rings by transverse furrows, generally two in each body-segment.
Posteriorly it becomes narrow and ends in the median groove about the last bristle-bundle.
Besides, a .glandular belt occurs at each side in the line of the bristles, after the
manner of the corresponding belt in the Maldanidæ, and it is continued backward
considerably behind the bristles.
Immediately within the lips is a rugose internal surface, then a membranous fold
slightly posterior to a line drawn between the third branchiæ.
The oesophagus (a, Plate CXIX, fig. 8 a) is pale, of considerable length, and terminates
in an enlarged region (stomach) posteriorly. At this point is an elongated glandular
organ, ƒ, which commences in front as a double duct with fatty granules and yellow
pigment, and enters the alimentary canal dorsally at the termination of the oesophagus.
The sac in spirit is filled with a whitish pulpy secretion. In some it appeared to have
two ducts opening into opposite sides of the tract. The duct seems to run a short
distance along the muscular coat before entering the canal, as in the case of the human
gall-bladder. Behind the foregoing is a delicate membranous region, g, somewhat wide
in calibre, and containing fatty flakes, followed by h, which has a tesselated yellowish
appearance from the chloragogenous coat. Then comes i, a rounded, muscular portion
of the gut, and m, the intestine, marked by longitudinal lines ending in the terminal vent.
The microscopic appearances of the intestinal tract at g and h do not indicate much
difference in function. Dr. Williams thought the anterior region -had a salivary function,
but he does not allude to the long cæcum, ƒ. The smooth muscular portion, i, has a
glandular lining of columnar cells closely arranged. The external wall of this part
consists of a mass of non-striated muscular fibres, circular and longitudinal.
In front the ventral wall of the body is covered with a dense series of glands, 6,
secreting the mucus for the tube, and the five segmental organs, c, which have a clavate
outline. They are filled with granules of various sizes. Each is connected with a tough
thread emerging from the glandular masses on -the ventral surface of the cavity. The
ventral blood-vessel, p, lies below the gut, and a branch, probably from the dorsal, runs
down the middle of the region in front of the oesophageal collar. Two detached glandular
pinkish bodies, o, hang by their ends to the body-wall about the posterior third, and
apparently send ducts backward—indeed, a double glandular structure seems to
extend to the posterior end. The contents are minute granules. Here and there the
glandular structures are connected by a finely reticulated network of vessels with curved,
fusiform pinkish sacs attached by the ends to the wall of the body.
The intestine behind the muscular portion is marked externally by yellowish striæ
apparently of a fatty nature, and these peel off readily like similar tissue in the muscular
region of the intestine.
The first segment is very narrow, and is enveloped laterally by the free collar of
the next segment. It bears the first pair of branchiæ, and forms a narrow rim in front
of the glandular ventral shields. The next has a greatly developed anterior lamella
or collar which stretches from the edge of the ventral shield almost to the second
branchia, thus forming the second process of this kind on each side. The following
segment has the third branchia and the first bristle-tuft, but bears no hooks. The bristles