with the anterior ènd. Kinberg’s figure differs, therefore, considerably froin British and
other examples—bothismall and large—that have come under observation; indeed, it is
more or less diagrammatic.
The entire ventral surface, including the feet, is studded with olosoly sot globular
papillae.:.
The papilla of the segmental organ begins: on the seventh foot as a small process,
becomes a free tubular structure on the ninth, and extends to the twenty-ninth fpot. The
papilla is comparatively large and long.
DigestipO System,—The extruded proboscis has at itB extremity a densely villous
border, divided into two by a bare, papilla at each side. The long processes (papillae)
are divided dichotomously (Plate XXXVII, fig. 2) in a very regular manner, about five
times from, the base. The great proportional size of this organ—for it is more than half
the length of the preserved f o rm - || a noteworthy feature, and indicates its importance
in the economy of the animal.
The pre-gastric ca3ca have their terminal appendages even more conspicuous than
m A. aculeata. The intestinal ceeca arise from the dorsal aspect of the gut close to the
median vessel. They thus slightly differ from those of Aphrodita and Bermione. In
regard to the arrangement of the terminal caica, they approach those of the former.
In the Zetlandic examples masses of mud and mucus in the stomach were very-rich
m Foraminifera, sponge-spicules, radiolarians, diatoms, bristles of Annelids (Spionidm),
and fragments of crustaceans.
• Males.—Fifteen pairs, smooth, somewhat pellucid, and-slightly iridescent. - They
are more or less rounded or ovoid, and with the exception of the first two are
attached by the centre of the outer border as in Aphrodita and Bermione:. While .the
first pair are small, they rapidly increase in. size, the middle Third of the bódy having
only three or four large scales. They oeeur on segments 2, 4, 5, 7, and so on to 23 25
28, and 31.
• FeetM ^ he l0°g’ brownish’ iridescent spines which flank the sides are flattened and
flexible, with the tip Somewhat abruptly tapered in lateral view (Plate XXXVI, fig. 8),
whereas when seen on the flattened face the sides have four or five recurved teeth (Plate
XXXVI, figs. 4 and 6). The majority have three teeth o‘n each side (Plate XXXVI, fig.
12), but some have four. The barbed bristles have guards or sheaths, or traces of these
in the preparations (as in the figure), but whether they are only perfect in the young condition
of the bristle is unknown. They seem to be removed readily.1 The main part of
the shaft is flat, broad, longitudinally striated, and it somewhat diminishes inferiorly, and
terminates m a flattened, blunt extremity, to which the muscles are attached. For some
distance above the base the shaft is paler, and shows a central band as if from an axial
cavity. The spines present a distinct curvature. About twelve well-marked groups of
the long spines occur in a good example. These spines retain the same essential
structure posteriorly.
The first pair of feet are directed forward, and bear the tentacular cirri (which
are much longer than in Aphrodita aculeata). Each has two tufts of pale, simple bristles,
Perfect examples occasionally adhere to the felt.
which taper to a fine hair-like point. Their outline seems to be smooth, though sandy
débris lodges readily amongst them. The anterior tuft is directed forwards and inwards
as an expanded fan, while the compact posterior, one goes inwards and backwards. A
strong spine supports the foot. The bristles are similar but somewhat stronger dorsally
in the second foot. In the third foot a more slender series of bristles occurs to the
exterior of the cirrus, while a stronger series is dorsal. This and the next have
pinnate bristles in the ventral division.
The fourth foot, which is provided with a ventral cirrus, has in the inferior division
a tuft of pale pinnate bristles, like those of Aphrodita. The same pinnate bristles occur
in the fifth foot, adjoining the ventral cirrus, while*above them are a few of the ordinary
kind -with feathered tip and hook. In the sixth only the latter are present. The typical
forms are shown in Plate XXXVI, f ig s 5 and 7.
In the same way the last foot or two have a modification of the ventral bristles, for
the spikes above the hook are short and distinctly separate. Moreover the last foot has
pinnate bristles as in front, along with an ordinary form or two.
The feet appear to be about thirty-four, the dorsal division alternately bearing cirri
and long bristles.
The dorsal cirri spring from the centre of a fringe of the more slender bristles, their
places being taken in the scale-bearing segments by the long hooked spines. In the
case of the cirrigerous feet a group of stout, short, brownish bristles occurs in front of the
cirrus, and a somewhat longest* and stronger series springs in the scale-bearing feet on
the dorsal side of the long spines. All are densely covered with a muddy and sandy
investment, but their surface appears to be smooth.
A typical foot, e. g. one bearing the long dorsal spines, has dorsally (from within
outward) the slender hairs which form the felt, then a group of short stiff bristles, followed
by the papilla carrying the long brown spines, which have a distinct curve. A
tuft of delicate bristles occurs beneath. The scale is fixed posteriorly. After an
interval the ventral branch of the foot bears the semi-pinnate bristles and the ventral
cirrus.
The last pair of feet are rudimentary, and lie in ordinary positions behind the anus,
which is dorsal.
The segmental organs (nephridia) point upward between the feet, and are as well
developed as in Aphrodita aculeata.
A Norwegian example, sent by Dr. Merle Norman,1 shows guards to the front of the
dorsal spines, and a slightly hastate tip beyond the barbs. The ventral bristles seem to
have shorter tips.
A series of small specimens occur from North Unst—from 5‘5 mm. upwards. These
have pale spines and bristles, yet all the bristles and the dorsum are densely coated with
sand-grains. They were captured in July, and probably represent the growth since the
previous spawning season.
Loxosomæ are common in this species on the feet, ventral surface, and on the
dorsum under the scales.
1 Op. cit., p. 171.