1915. Sdbellaria spinulosa, Allen. Journ. M. B. A., vol. x, p. 645.
1917. „ „ . Rioja. Annel. Poliq. Cantâbrico, p. 43.
1919. „ „ . var. Intoshi, Fauvel. Arch. Zool. Expéiv, t. lviii, p. 449.
„ „ „ idem. Bull. Mus. Hist. Nat., No. 6, p. 477.
Habitat.—Masses of the tubes cover rocks and shale about half-tide-mark near the
commencement of the East Rocks, St. Andrews, and elsewhere. They also occur on the
roots of tangles and on shells and stones from deep water. Berwick Bay (Dr. Johnston) ;
Southport (Dr. Carrington) ; Luccomb Chine, Isle of Wight, between tide-marks ;
occasionally on oysters off ^t. Peter Port, Guernsey; Lochmaddy, North Uist, under
stones near low water-mark, not common (W.C.M.) ; Plymouth (Allen and Crawshay) ;
Dublin Bay (Southern). Whereas at St. Andrews it forms large spreading masses
between tide-marks, its place is taken at Hilbre Island by S. alveolata, and S. spinulosa
there is said to be a form from deep water. Southern states that it also is usually found
in deeper water in Dublin Bay, whilst on the West Coast it is littoral as well as
laminarian in distribution.
Abroad it is found in Sweden (Lovén), Heligoland (Leuckart), French coast (De
St. Joseph), St. Thomas and Madagascar (Fauvel).
The cephalic region in Sabellaria spinulosa {Plate CXVIII, fig. 3 a) is. divided
dorsally into two great lateral lobes bearing the paleæ on pillars, the dorsal edge of the
mouth being in the centre, whilst the lips slope obliquely backward ventrally ; the two
lobes, which appear to be homologous with the operculum of the Serpulidæ, can be widely
separated ventrally, where they merge into the mouth and its tentacles. Arnold Watson
found three sets of cilia on the tentacles : (1) A series of long cilia, arranged at intervals
in pairs, driving particles into the longitudinal groove ; (2) with these are palpocils which
remain extended after the former cease 1 ; (3) a shorter sériés of cilia in the tentacular
groove. Each lobe forms a semicircle, which by apposition with its neighbour constitutes
the opercular crown on the dorsal arch of the mouth, and between the tentacles is- a
tongue-shaped fold or process—richly ciliated.
The external series of golden paleæ which form a fringe to the crown are about
twenty-five in number, the typical paleæ (Plate CXXIIJr, fig. 2) having a shaft,
which tapers from the junction of the tip to the pointed base. The tip forms a broad,
flattened, and somewhat spatulate process, one side of which bulges more than the other
immediately on expanding above the shaft, whilst the tip is symmetrically narrowed to a
blunt point, which is cut into three spikes on each side, the centre being produced as a
long process with three lateral spikes directed distally. In the examples from Luccomb
Chine, Isle of Wight, these lateral spikes are smaller and more numerous, and the
process is larger. Striæ cross the flattened tip from side to side, and are slightly curved
upward at each end, the bulged base of the tip often showing a differentiation of these
and a more marked curvature. The paleæ at the extreme ends dorsally and ventrally
are less neatly formed than those in the centre of the semicircle, the inner lateral
spikes being long and powerful, whilst the central elongated process is more or less
1 Ihe cilia themselves often x*emain quiescent, so that it might be difficult to distinguish the one from the other.
rudimentary. All, however, have the asymmetrical base as in the other types of the
second and third rows.
The second row consists of modified bristles with a slender shaft tapering to a
point at its base, and of a proportionally massive tip shaped like a broad bill-hook
(Plate CXXIII, fig. 2 a). The shaft tapers from its upper end to its pointed base and is
comparatively slender. It curves posteriorly into the convex margin of the tip, whilst
anteriorly it abruptly expands into a thin edge, which is concave in its progress to the
pointed tip. Moreover, a second outline occurs within the foregoing, so as to simulate
a double edge, as if a trace of a double wing were present. The thin edge beyond the
inner line is boldly striated transversely throughout, and curved transverse striae cross
the greater part of the tip, but not the base. A shorter series of these bristles also occurs
(Plate CXXIII, fig. 2 b).
A considerable number of the bristles in this (second) row present a further stage in
the modification of the tip, which forms a long, curved, tapering structure with the
double outline on the anterior face and the transverse striae throughout the greater part
of its extent. The two ridges on the anterior face are evidently modifications of wings,
and the point is acute. The shaft is long and tapers from the upper part to a point at
the base, whilst the posterior curve comes off distally before the anterior and is less abrupt.
The anterior outline swells into the “ heel ” of the tip and is specially striated. In the
St. Andrews forms these chiefly occur at the ventral edge. In those from Luccomb
Chine, Isle of Wight, they occur all along the second or middle series.
In the variety ensifera from Lochmaddy and Guernsey several of the pale* of the
second row form long needle-like processes projecting far beyond the rest, and giving a
character to the crown. Such occur in the young as well as in the adults from both
places. Fauvel found a similar variety at St. Thomas.
The third or inner row has another modification, the tip leaving the thin shaft at an
angle greater than a right angle, and resembling a long foot with a pointed toe, the
resemblance being the closer since the heel and foot have a different axis from the shaft.
The shaft is proportionally the most slender, and the bending of the tip backward
causes the heel (anterior projection) to stand out prominently. Bold transverse stri*
occur on the face between the ridges, so as to make a rasp-like surface to which
mud adheres. Finer strige are found on the heel and on the tip apart from the ridges.
These bristles form a spiny guard to the oral aperture, and are often covered with
muddy debris.
The crown is supported on a firm fleshy pillar, slightly bifid dorsally, and more
distinctly so ventrally, its surface dorsally and laterally being variegated with purplish or
madder brown pigment—often arranged in bands dorsally and at the sides of the tentacles
ventrally. A circle of acute tapering and highly sensitive (Arnold Watson) papillge
pointing forward surrounds the base of the crown, and a brown pigment-band passes
from the sides ventrally to the fissure.
Amidst the pale* of two specimens from Southport are numerous examples of a
parasite akin to Udonella.
In the Scottish forms variations in the length of the tips of the second row of pale*
are not uncommon, two or more of these on each side occasionally forming conspicuous