of oysters, and some construct mucous tubes with fragments of shells. Some are phosphorescent.
They described thirteen species of the genus.
The Polynoidæ were included by Kinberg (1857) under his third family, Polynoina.
His diagnosis was :—Elongated body ; no facial tubercle ; convex cephalic lobe with the
base of the tentacle from the middle anteriorly ; two antennæ ; four eyes ; palpi thick.
Pharynx exsertile, cylindrical, without long papillæ; horny jaws. Scales twelve to
thirty-five pairs. Segments bearing elytra devoid of cirri. He gave six genera, viz.
Lepidonotus, Halosydna, Antinoë, Earmothoè, Hei'madion, and Polynoè, the second, third,
fourth, and fifth being new.
Michael Sars (1860) reviewed the condition of the Polynoidæ, as shown by (Ersted
and the subsequent writers up to date, and gave a list of the northern examples with.new
species, viz. P. nodosa, P. asperrina, P. ra-rispina, and P. scabriuscula.
De Quatrefages (1865) described the Polynoidæ as having a very distinct head,
furnished with three antennæ and four eyes. The buccal segment is characterised by the
presence of two pairs of tentacles, the superior being bifurcate, the much longer and
larger inferior, simple. The feet are more or less biramous, but the setigeous processes are
united to a common base. Elytra altërnating with superior cirri, and covering the back
throughout. Proboscis armed with two pairs of horny jaws.
In his remarks on the tribe of the Polynoidæ Claparède (1868)1 criticises the great
increase in the genera caused by Kinberg and Malmgren. Thus the former subdivided
the genus Polynoë of Savigny into six, taking as his basis of classification the position of
the lateral antennæ ; the number of the scales ; the fact of their covering more or less of
the dorsum ; and the length of the body. Malmgren again augmented the number of
the genera by nearly as many more as Kinberg, so that the original genus of Savigny
was multiplied nearly twenty-fold. Claparède points out that the objections of Sars to
the methods of Kinberg apply equally to those of Malmgren, because he not only
employs the same elements in classification, but adds others of less value, such as the
structure of the terminal parts of the ventral bristles. He shows that, for instance, the
same species of Syllis presents features which would appear to subvert the reliance to
be placed on this method, since the compound bristles are often replaced by simple
bristles. There is, however, more in the systematic study of the bristles than Claparède
imagined. Claparède grouped the Polynoidæ as one of the Tribes of his family Aphro-
ditiens, Sav. (sens str.).
In his supplemental volume he correctly indicated, under Eermadion fragile, the
position of the nephridia and their function as channels for the extrusion of the reproductive
elements.
Grube, in his ‘ Annulata Semperiana,’ gave the following description of the genus
Polynoè. Body oblong or elongated, flattened and vermiform; segments more or less
numerous, second, fourth, fifth, and every alternate segment to the twenty-third bearing
elytra, the intermediate ones having cirri. The segments after the twenty-third have
scales on every third foot or they are absent, rest bear cirri. Cephalic lobe rounded,
more or less bipartite ; two pairs of sessile eyes, three tentacles, two subtentacles (palpi).
Buccal segment with two tentacular cirri, no setæ ; two bundles of bristles and two cirri.
1 Ann. Nap.
Ventral cirrus twice as long as pinna, set* simple, two anal cirri. Elytra covering
dorsum or leaving it bare. Pharynx with a crown of simple papillaa. Jaws horny, not
denticulated. He grouped the species chiefly according to the arrangement of the
tentacles, the number of the elytra and their structure, with a few additional particulars.
The account is thus more detailed than that of 1874.
G. Darboux1 fils distinguishes in the dorsal cirrus the cirrophore and the cirrostyle.
The former is an evagination of the entire musculo-cutaneous envelope. The cirrostyle
is inserted on the cirrophore by a delicate epidermic membrane. A secretion, he says,
fills a glandular pocket at the insertion and causes a strain so that rupture ensues.
Whether as a family or a sub-family the Polynoid* are sufficiently distinguished
from the Aproditidas by the shape of the body, the absence of a facial tubercle, the
diminished size and the chitinous armature of the proboscis, the reduction in size of the
alimentary caeca, and the position of the segmental (nephridial) papillae.
They are cosmopolitan forms, yet each area has its characteristic species. Thus in
Britain such as Eupolynoe anticostiensis, McL, Melsenis Loveni, Mgrn., and Eucranta
villosa, Mgrn., are absent, while they are found in more northern latitudes.
Commensalism is not uncommon in the group; thus Dr. Baird found Earmotthoe
cvrrata (?) in the tubes of Ghcetopterus, Gattyana cirrosa is common in the tubes of
Amphitrite, Polynoe scolopendrina in tubes of Terebella nebulosa. Malmgrenia and Acholoe
occur on Echini and starfishes (Astropecten), and Earmothoe in Euplectellse. Dr. Baird
notes that Mr. Lord found at Vancouver’s Island a Lepidonotus coiled under the foot of a
Fisurella, and another on a starfish. Verrill,3 again, mentions an orange-red Polynoe
which occurs amongst the tentacles of the anemone, Bolocerd Tuedise, and another species
with a dark purple proboscis and finely spinulose scales is very abundant among the
branches of Acanella Normani. Dr. H. J. Johnson adds two species to the forms living
as commensals, viz. Polynoe reticulata, in tubes of Amphitrite and Thelepus, and P. gig as
in an Amphitrite, both from the Pacific coast of California.3
Genus VIII.—Lepidonotus4 (Leach, 1816), char, emend.
Body short, more or less linear. Anterior part of the cephalic lobe produced into
the bases of the median and lateral tentacles. Palpi smooth or with papillae in five
longitudinal rows. Three comparatively short alimentary caeca directed forwards into the
peri-pharyngeal space. Elytra, twelve pairs, covering the dorsum entirely, and occurring
in segments bearing feet thus : 1, 3,4, 6, 8, and so on to 20, 22. Bristles of the superior
lobe slender, serrate, shorter than the inferior, which have a smooth portion below the
slightly hooked tip, and then a spinulose region beneath. Nerve-trunks in the granular
layer of the epiderm, between the powerful oblique muscles.
i C. R., 126 (1878), pp. 257-8.
8 ‘ Albatross ’ Explorations, ‘ TT.S. Fisheries "Report/ 1885, p. 525.
8 ‘ Proceed. Calif. Acad. Sc.,5 1896, 3rd ser., vol. i, No. 5, p. 1/0, &o.
4 Kinberg (op. cit., 1857) gives as a diagnosis of the genus :-|§ Anterior part of the cephalic
lobe produced into the bases of the tentacle and antennas; pharynx with papillae; jaws; elytra
covering the dorsum entirely; body short.” Nothing special can be made out of his remarks on the
jaws and tentacular cirri.