and Amphictene rested only on secondary characters. Pectinaria was characterised by
Malmgren as having an entire fleshy cephalic region and the tube straight.
Meyer1 (1887) remarks that at Naples the Amphicteniens are normally hermaphrodite.
The Amphict^nidse formed, along with the Ampharetidas and Terebellidas, Levinsen’s
group Terebelliformia (1883), after the arrangement adopted by Malmgren and others, and
there- is some justification for this view. He included all the Amphictenidse under the
genus PectinaHa.
The circulatory and digestive systems of Pectinaria belgica., Amphictene auncoma and
Petta pusilla were carefully described and figured by Wiren3 (1885).
Fauvel3 (1903) describes the form and structure of the tubes of the Ampliictenidae,
the glands supplying the cement and the habits of the annelids. He subsequently (1907)
gave an .account of the circulation in Lagis Koreni: The account- of the intestinal sinus,
the large size of the ventro-pedal vessel of the first and second segments, and the occurrence
of contractile ampullae on them, the structure of the heart, and the indirect
communication of the intestinal circulation with the ventral trunk are amongst the
salient features of this paper.
The Amphictenidse were placed after Terebellides at the end of the family
Terebellidae by Dr. Johnston (1865).
Three pairs of organs of Bojanus are described by Cosmovici (1880) in the anterior
region of the body of the* Amphictenidse. The first pair have the form of closed glandular
pouches. The other two are attached to the segmental organs, which are flask-shaped,
with a posteriorly directed funnel-shaped internal opening and an external pore. The
backwardly directed internal aperture is considered by the author to be related to the
position of the genital products which lie on each side of the nerve-cord posteriorly.
D. Nilsson4 (1912) gives a detailed account of the nervous system and sense-organs
chiefly of this family, and he contrasts the arrangement of the cephalic ganglia of the
Amphictenidse and Ampharetidse with those of the errant forms—all being essentially
three-lobed, as Pruvot and Racovitza showed. Whereas, however, the ganglia in the
free-living forms are arranged (diagrammatically) like an H or a K, those of the two
families mentioned are in the form of a crescent. He describes in the branches of the
nerve-cord of Pectinaria belgica a motor dorsal and a mixed ventral root, and he gives a
figure showing both segmental and intersegmental nerves to illustrate this condition.
The former (dorsal) root supplies the longitudinal muscles, the latter (ventral) the circular
muscles and sensory structures. Further observations on this subject would be interesting.
Nilsson’s account of the nervous system and sense-organs specially deals with Lagis
Koreni, Pectinaria belgica, Amphictene auncoma and Petta pusilla, and he points out that
the scapha (with its eyes in Petta) has its nerve-rsupply from the posterior gastric just as
the buccal region has its nerves from the stomato-gastric. The fine nerves on the veil,
and the nerve-cells of the nuchal and side organs are figured and described. Finally he
V ‘ Mittheil. Zool. Stat. Neap./ viii.
3 ‘ Kongl. Sv. Yet. Akad. Hand]./ Bd., xxi, p. 22, etc., Taf. iii, figs. 1—5, Taf. iv, figs. 9, 10,
Taf. v, Taf. vi, figs. 8, 9.
3 | Mem. Pontif. Accad. llomana N. Lincei/ vol. xxi, pp. 1—28, with text-figs.
4 ‘Zoologiske Bidrag Uppsala/ p. 85, Taf. iii—v, 1911—12.
discusses the homologies of the cephalic ganglia with the succeeding segmental ganglia
of the main cord.
In his dredging expedition to Finmark, Canon Norman procured numerous Polychaets,
which lie kindly sent me for identification. They included many of those described in
the present volume, such as Amphictenidse, Ampharetidae, Terebellidas, Sabellidas and
Serpulidse. The list was published in the ‘Annals of Natural History,’ 7thser., vol. xii,
p. 283 (1893). It has been deemed sufficient to note them under the head of “ Distribution,”
and the same applies to Kiikenthal’s Polychsets from Spitzbergen as entered by
Marenzeller and E. Mayer in the ‘ Arch. f. Naturgeschichte ’ for 1889, pp. 1 and 132..
C. Hessle 1 furnishes a detailed account of the Terebelliformia of Levinsen, with
plates and text-figures, and in this the Amphictenidse are included systematically and
anatomically. His descriptions and figures are good, and he has illustrated by a series of
diagrams the typical nephridia in each family. He treats not only of the European, but
of the extreme northern and southern Polar types, those from Japan, the Swedish
Expedition to Magellan, and the collections in various museums to which he had access.
The Amphictenidse are dwellers in sand or fine gravel, though in deep water a few
frequent the mud, making their tubes of sponge-spicules artistically and regularly
arranged in a transverse manner. They are nocturnal in habit, and widely distributed.
The northern Gistenides hyperborea, so common in the Gulf of St. Lawrence, Canada,
has not yet been met with in Britisjr seas. The group has affinities with the Ampharetidae
and the Terebellidas, and Levinsen and others form these into Grube’s division Terebelliformia.
Genus CXXXIV.—P ectinaria, LamarcJc, 1812.
Gistenia, Leach; Amphictene, Savigny.
Cephalic lobe rounded; frontal veil (tentacle-membrane of Hessle) cut into triangular
fimbriae. Tentacles short, covering the cephalic lobe. Two eyes over the ganglia.
On the second segment is a cirrus. Buccal segment extending as a nuchal area with its
paleae. Body broad in front* tapered posteriorly and of two regions, the anterior much
the longer—branchiferous and setigerous; segments about twenty; posterior region (scapha)
of six short segments containing the anus, armed with minute paleae and crenate or
“toothed,” on each side. Branchiae two pairs, on the third and fourth segments, comb-like
in form, with broad teeth (lamellae). A pair of cement glands in the fourth segment.
Nephridia in the fourth, seventh and eighth segments, the anterior longer than the
posterior. Seventeen pairs of bristled-bundles, beginning on the fifth segment. Bristles
capillary with narrow wings. Uncini pectiniform, with several large teeth, and with
smaller below. They commence on the eighth segment and continue to the last. Tube
composed of neatly arranged and minute fragments of shells, grains of sand, straight
or slightly curved.
‘ Zool. Bidrag Uppsala/ Bd. v, 19-17.