Reproduction.—Ova of considerable size are present in examples dredged by Dr.
Gwyn Jeffreys off North Unst in June, 1867.
Kinberg (1857) characterised this species as having a rounded cephalic lobe, tripartite
from two curved sulci, filiform tentacle longer than the palpi, and the median
elytra reniform. I t was procured on the western and northern shores of Scandinavia.
Ehlers (1875) considered the Lsetmatonice Kinbergi of Baird as different from
Kinberg’s L. filiformis, but, as previously stated, there is no reason to doubt their
identity.
Ehlers (1887), in his ‘Annelids of the United States Expeditions,’ considers, as he did
in the former publication (‘ Annel. of the ‘ Porcupine ’ ’) that he is still dealing with a
new species fide Baird. Only a single form appears to occur in British seas, and it extends
to Norway and the American coast. His figures are the work of an artist, and thus the
scientific accuracy is not beyond doubt, as a glance at the dorsal spine of his pi. viii,
fig. 3, demonstrates. The peculiar flattening of the main part of the shaft, and the
characteristic narrowing of the tip, have been overlooked. This form, however, may be a
variety of L. producta, allied to L. prod., var. benthaliana. His description gives nothing
diagnostic.
2 . LiETMATONiCE PBODOCTA, v a r . Britannica.
Specific Characters.—Body ovate-oblong, of a pale flesh-tint, and devoid of dorsal
felt. Scales pale, their reticulate cordate structure being better marked than in any
other form. Segments forty-five. Head triangular; ocular peduncles globular at the
tip, narrowed inferiorly at the peduncle; no eyes. Lateral process at the posterior
part of the head smaller than in the typical forms. Papilla? of the angular facial tubercle
more lobate than in L. producta. Glochidiate bristles with four recurved fangs, besides
the process at the base of the terminal spear-tip. Yentral bristles with stiffer basal and
more slender distal pinna?.
S ynonym.
1894. Lsetmatonice producta, Flor. Buchanan. Proc. Roy, Dubl. Soc., vol. viii (n. s.), ii, p. 169.
Body more or less oblong, of a pale flesh-tint, devoid of dorsal felt, scales pale; forty-
four bristled segments, which increase to the middle or behind the middle of the body,
and again diminish posteriorly, though the latter region is somewhat blunt. The centre
of the head is more or less triangular, with a prominent swelling, and bearing in front
the two ocular peduncles, which are globular at the tip, but have a distinct, peduncular
portion, thus differing from those of var. Willemoesii, which ape more or less sessile, and
without a trace of eyes. Those of L. producta are more elongated. The lateral process
towards the posterior part of the head is much smaller than in L. productairom. Kerguelen.
I t forms a lobate flattened process in the latter, and nearly reaches the base of the
ocular peduncles. On the other hand, in the British specimens it is only a small papilla,
touching the base of the lateral cephalic swelling. I t appears to be the rudiment of a
scale-bearing process. The ridge from which the tentacle arises extends backwards in
the middle line, and at the posterior border of the head it bends outward on each side
to bear the papilla, viz., the modified scale-bearing process. The papilla? of the facial
tubercle are more lobate than in L. producta from Kerguelen, and proportionally less
elongate. The palpi are, so far as the specimens go, less powerful than in L. prod/ucta
from Kerguelen, but the difference in regard to the papillae or spikes is small. Both
have numerous papilla? as in L. filicornis. All that can be said is that perhaps they are a
little more numerous towards the tip of the palpi of L. producta from Kerguelen. The
. tentacular cirri are somewhat longer than the tentacle, and their tips are rather more
elongate than in L. filicornis, while they are shorter than in L. producta from Kerguelen.
The segmental papilla? begin on the posterior face of the fifth foot, and extend to the
thirty-eighth. They form flattened processes somewhat more distinct than in L.producta
from Kerguelen. Besides, in the latter form they begin on the tenth foot, and extend to
the thirty-ninth.
The papilla? of the proboscis (Plate XXXVII, fig. 3) have broader tips than those of
L. filicornis, and are less regularly dichotomous. The tips are sometimes divided into
three, and occasionally are ovate, clavate, or irregularly lobate. There is not much
ground for calling the thickened regions of this organ parts representing maxilla?, as
Grube does.
No specimen is in a condition to give a reliable opinion of the arrangement of the
dorsal spines. The papilla? bearing them are a little more prominent than in L. producta
from Kerguelen, but this may be due to their condition, for they have evidently been
subjected to considerable hardships. They probably spread, in the scale-bearing feet,
over the dorsum as in the forms from Kerguelen, the feet carrying cirri having dense
groups of more slender bristles.
The structure of the first two feet agrees with that in the form from Kerguelen.
The other feet are also similar in structure. The tips of such of the long dorsal spines
as were present agreed with the figure (Plate' XXXVI, fig. 4), which shows a spine
slightly turned to the left, four recurved fangs occurring on each side, besides the point
at the base of the spear-like tip. The ventral bristles (Plate XXXVI, fig. 5) conform
mostly to the type of L. producta, var. Wyvillei, having somewhat stiffer (stouter) basal
bristles and numerous slender distal ones.
In describing this form in the Annelids of the ‘ Challenger,’ I for some time had the
varieties ranged under separate species, distinguished by certain evident characters.
The reticulate cordate structure of the scales is very well marked (apparently better
than in any other species), forming a series of wavy lines like those on the sand of the
sea-shore.
No parasitic Loxosoma? occur on this form, yet foreign varieties abound with them,
such as L. producta, var. benthaliana, on which the remarkable new gymnoblastic
hydroid, Stylactis vermicola, described by Prof. Allman, occurs on the under surface of
the scales of this inhabitant of the depths (2900 fathoms) of the North Pacific.
The species was first procured by Prof. Haddon during the Royal Dublin Society’s
Survey, on a bottom of sand and gravel at a depth of 500 fathoms, fifty-four miles off
35