but the hook seems to differ from that of the species mentioned if one may judge from
the British examples.
The posterior hump of the hook seems only to be fully developed in adult specimens,
as in a small example from Norway the posterior outline of the hook was straight except at
the lower end where the ligament was fixed, and -this seemed to be less fused with the
base than in the adult. The posterior hooks did not show noteworthy differences from
those of the adult. In this example the body was terminated posteriorly by a large
rounded papilla budding out on each side from what apparently was a ruptured tail.
The tube is massive, composed of a thin lining of secretion and a thick coating of mud
interspersed with minute stones and fragments of shells, generally arranged transversely.
The translucent fragments permit a certain amount of light to pass into the tube. In
some localities the tubes are formed of a thick layer of secretion and mud, amongst
which the small stones are carefully imbedded, and in several the smaller stones are
selected for the area near the transverse slit or valvular aperture. This end is elastic,
the slit forming a curve convex on one side and with a concave slope on the other, and
the symmetrical arrangement of the ends of the slit is noteworthy, a short fold at right
angles to the main slit occurring at each side. It is not yet proved that these tubes
found by the “ Porcupine ” of 1869 are those of Pista, since no trace of the inhabitant
was present. De St. Joseph found the tubes frequently on Bytiphloea pinastroides in
deep water, and composed of a transparent secretion covered with clear grains of sand
and pieces of algae. His species, however, differs.
0. F. Muller’s description and figures of this species are easily recognisable, especially
the figures.
Montagu’s figure of the annelid (by Miss D’Orville, 1808) shows two narrow tufts
of branchiae, but is probably intended for this species.
The Terebella maculata of Daly ell1 (1853) somewhat resembles Pista cristata, but as
he does not refer to the minute structure of the branchiae, which rather agree with those
of Nicolea venustula, especially if the “ two pellucid stumps ” represent traces of developing
branchiae, there is doubt, more especially as his Terebella pecten2 agrees in regard
to the branchiae with a young Pista cristata.
The Terebella flexuosa of Grube,8 from Greenland, has only a single pair of branchiae,
but they have a series of comparatively simple branches, and there are fifteen pairs of
setigerous processes instead of seventeen, as in Pista.
De St. Joseph (1906) thought this form approached Thelepus setosus, De Quatrefages,
and gives reasons.
Fauvel’s4 Eupista dibranchiata has a hook very like that of P. cristata.
Genm CL.—L a ph a n ia , Malmgren, 1865.
Cephalic lobe truncated, with a horse-shoe-shaped plate over the mouth ; grooved
tentacles of moderate length. No eyes or branchiæ. Buccal segment a little elongated
1 ‘ Pow. Créât./ p. 203, pi. xxviii, figs. 10—13. 2 Op. cit., p. 208, pi. xxvi, fig. 9.
8 ‘ Archiv f. Naturges./ Bd. xxvi, p. 102, Taf. v, fig. 2.
4 ‘ Campag. Monaco,’ p. 303, pi. xxviii, figs. 1—12.
and separated from the vent by a groove. Body slender, somewhat enlarged in front,
gently tapered to the posterior end, where the segments are longer. Seventeen pairs of
capillary bristles, commencing on the third segment. The smooth bristles have winged
tips, and some with shorter tips are almost geniculate. Avicular hooks commence on the
seventh (Hessle ninth) setigerous segment in a single row; then a double row between
the eleventh and twentieth, continue to the posterior end, and show four teeth above
the main fang. Distinct ventral scutes. Anterior nephridia reduced, the first of the
posterior in the fifth segment, and opening through the diaphragm, the rest nearly
equally developed, with long tubes.
1. L a ph a n ia bcboki, Malmgren, 1865. Plate CXXVI, figs. 4—46—bristles and hooks.
Specific Characters.—Cephalic lobe as in the genus; buccal segment somewhat
elongated1';.! the second the largest, and separated from the third by a groove and
sometimes a ridge. Body 50—70 mm. long, and fifty segments, enlarged in front, and
gently tapered to the posterior end; about two inches or more in length.. It is rounded
dorsally in front, but by-and-by the lateral regions form prominent fillets which cause a
moniliform condition posteriorly. About ten to twelve conspicuous ventral scutes. Tail
unknown. Bristles on seventeen segments, pale golden, with tapering, winged tips,
those with shorter tips being winged and almost geniculate. Hooks avicular with four
teeth above the main fang in lateral view. Nephridia in the fifth, sixth, seventh and
eighth segments, a rudimentary one (Fauvel) between the third and fourth segments.
Tube of mucus and sand.
Synonyms.
1865. Laphania Bcecki, Malmgren. Nord. Hafs.-Annul., p. 386.
1867. ,, „ idem. Annul. Polych., p. 110, Tab. xii, fig. 68.
1873. ,, ,, Willemoës-Suhm. Zeitschr. f. wiss. Zool., Bd. xxiii, p. 349.
1883. „ ,, Levinsen. Yidensk. Meddel. nat. For. Kjtfbenhavn, p. 178.
1893 ?. Amsea trilobata, Lo Bianco. Atti R. Accad. Sc. Nap., vol. v, No. 11, p. 60.
1894. Laphania JBcecki, Bidenkap. Christ. Yet.-Akad. Handl., p. 131.
1899. jBpLv „ Ssolowiew. Ann. Mus. Zool. Acad. Imp,, St. Petersburg, t. iv.
1912. ,, „ Ditlevsen. Danmark Eksped. Grönl., Bd. v, p. 428, pi. xxix, figs. 10—15.
„ ,, „ Wollebask. Yidensk. Skrift. Krist., 1911, p. 108, pi. xxiii, figs. 1—-5.
1915. ,, ,, var. hystricis, McIntosh. Ann. Nat. Hist., ser. 8, vol. xv, p. 25.
1917. „ ,, Hessle. Zool. Bidr. Uppsala, No. 5, p. 204.
Habitat.—Dredged off Shetland by Dr. Gwyn Jeffreys in 1867; “ Porcupine ” Expedition,
1870, Station I (Entrance to British Channel), in 567 fathoms.
Abroad it is found in the Gulf of St. Lawrence, Canada (W. C. M.); Finmark
(Malmgren); Greenland (Ditlevsen, Hessle) ; White Sea (Ssolowiew).
The cephalic lobe is so developed that at first sight this form has some resemblance
to a Maldanid. The dorsal collar, however, is present, and the plate passes obliquely
forward to make a fairly firm arch over the mouth. From the surface of the plate spring
1 As long as the three following (Hessle).