little tapered, and the latter with shorter spinous regions. The structure of the scales
corresponds with the typical form. The body is purplish throughout.
Habits.—They cling to the test near the mouth of Spatangus puipureus, and are thus
commensalistic forms.
Prof. Harvey-Gibson and Mr. Hornell found them on Astropecten irregularis—
between the rows of pedicels—at a depth of 20 fathoms in the Liverpool district.
The former gives an account of various structural features of this species.
2. M a l m g r e n ia a n d r e a p o l is , McIntosh, 1875.
Specific Characters.—Head less pyriform than in M. castanea, with anterior peaks
more or less adnate. Eyes smaller than in M. castanea; anterior pair wider apart than
the posterior. Median tentacle incomplete in all ; lateral tentacles small and subulate,
with two brown rings at the base. Palpi smooth. Tentacular cirri brownish, with a
few clavate cilia. Body elongate. Scales, fifteen pairs (?); first pair rounded, rest reni-
form or irregularly rounded. Those after the second pair with a brown ring more or
less complete, and at the sixth or seventh pair a V-shaped mark and a spot become
distinct. A belt of small papillæ (microscopic) occurs along the central region of the
anterior border and extends to the inner corner in the reniform scales. Tips of feet are
blunt and bifid ; dorsal division less developed than in M. castanea ; bristles slender,
slightly tapered, with a probe-like tip, and minute serrationsjm thé edge. Ventral
bristles long, translucent, with a tapering spinous region which is simple superiorly—
ending in a distinct knob, the next series with a secondary process beneath the clawlike
tip, and inferiorly a single knob. A few clavate cilia occur on the stout, brownish,
and tapered dorsal cirri. The ventral cirri are slender and tapering, reaching only a
little beyond the bases of the bristles, and have a few short clavate cilia.
p- S ynonyms.
1875. Malmgrema andreapolis, McIntosh. Invert, and Pishes, St. A., p. 117.
1876. „ ' „ idem. Trans. Zool. Soc., ix, p. 377, pi. lxvii, f. 20—23.
HaUtat.—Not uncommon in the débris of the fishing-boats from the off-shore
(E. and B.), on the west sands after storms (E. M.), and in the stomachs of cod and
haddock at St. Andrews (E.).
Head (Plate XXVIII, fig. 8) tinted with brown on each side in the preparations,
the pale median groove marking off the symmetrical coloured areas on each side. The
anterior peaks are more or less adnate, but still visible at the origins of the lateral
tentacles. The head is less pyriform than in M. castanea, the eyes are smaller, and the
anterior pair are wider apart than the posterior pair. The anterior eyes look forward and
outward. The median tentacle is incomplete in all. The lateral are small and subulate,
with two brown rings at the base ; they are not in a condition to show cilia if they are
present. The palpi are smooth. The tentacular cirri are brownish, and have a few
clavate papillæ. The pigment under the median tentacle is better marked than in the
former species.
Body rather elongate, more than an inch in length, and having about 36—37
bristled segments. In some the posterior region (about a dozen segments) is prettily
mottled in the preparations with dark brown pigment both dorsally and ventrally.
Occasionally the brown bars, sometimes with a pale centre, are best marked on the
ventral surface. Very little tapering of the body occurs anteriorly. The ventral surface
is for the most part pale and finely iridescent. The segmental eminence is prominent,
but a special papilla cannot be made out.
Scales (Plate XXXIII, fig. 11) probably fifteen pairs, but no specimen is complete.
The first pair are rounded, with a broad belt of madder-brown round the edge and a
spot in the centre, though in some the latter joins the outer portion of the ring. The
rest are reniform or irregularly rounded. The second scale in some has a brown ring
round the exposed part, and a patch near the outer border anteriorly, representing the
spot in the centre of the first pair and that of the scales behind. Those after the second
pair have a brown ring more or less complete, the broadest part being toward the inner
margin, and the spot at the anterior leg of the V-shaped mark gradually becoming more
evidently separated. About the sixth or seventh pair the V-shaped mark and the spot
become distinct. Posteriorly a tendency to the obliteration of the ring is observed, and
the spot becomes connected with the remnant of it at the inner border. In a few
the pigment in the posterior scales occurs in detached specks.
The scales appear to be smooth under a lens, but under the microscope a belt of
small papillae occurs along the greater part of the anterior and outer borders (where
the curve is). This belt is continued in the reniform scales round the anterior and inner
corner.
Feet.—As in the former species, the specimens seem to have lost the bristles in the
first foot.
In looking at the feet from the dorsum it is observed, in contrast with M. castanea,
that the tips are blunt and somewhat bifid, though the posterior process is less prominent
than the anterior flap. In profile, again (Plate XXXI, fig. 3), the foot has a greater
depth from above downward in proportion to its length, and thus the terminal cone is
shorter. The dorsal division is less developed than in the former species, and bears a
series of slender, slightly tapered, inconspicuous, translucent bristles, with a peculiar tip,
which forms a kind of rounded knob (Plate XL, fig. 27, representing one of the larger
bristles), of much interest when contrasted with the ventral forms, since it demonstrates
how closely the same type holds in both divisions. The serrations are minute, and leave
only a short portion of the tip bare.
The superior bristles in the ventral branch are long and translucent, have a long,
tapering, spinous region, with a distinct knob, like a probe-point, at the tip (Plate XL,
fig. 28). The spinous region quickly shortens in the succeeding forms, which show a
most interesting series of gradations from the first appearance of the secondary process,
the shortening of the probe-point and its gradual modification into a claw and a knoblike
tip with an oblique edge between it and the secondary process (Plate XL, fig. 29).
The spinous' region in these is comparatively broad and short. Then, as the spinous
region diminishes inferiorly, the secondary process shortens and disappears, the bristles
50