110 LAMELLIDOR1S LUTEOCINCTA.
Lamellidons, that is to say, non-retractile and simply pinnate. They are not numerous.
I could see only four distinctly, but there may be double that number in all.
The radula consists of thirty-four rows, each with a formula of 1 + 1 .0 .1 + 1. There
is no median tooth, but there appears to be in places a fold on the rhachis. The first
lateral is large and stout, with about six denticles rather more distinct than in Mr. Farran’s
plate. The outer tooth is a small plate which bears a distinct and well-formed hook.
This species was described by Mr. Farran under a new name as Doiis beaumonti, but
there can be little doubt that it is the Dons luteocincta of M. Sars, and, so far as its
structure can be determined, it appears to belong to the genus LameUidoi'is. Its coloration
is distinctive, but still it is possible that it may be immature.
CRIMORA PAPILLATA A. & H.
(Plate II, figs. 1—5.)
See Alder and Hancock 2, p. 263; and Alder 1, p. 74.
This species has been taken twice in Moulin Huet Bay, Guernsey, on zostera in
shallow water, but to the best of my knowledge has not been seen since 1865. In
external appearance it is not unlike EuplocamuSj though the papillae are smaller, more
numerous, and less branched. The buccal parts are unlike those of all known Polycerids.
The body is plump and limaciform, rising towards the branchiae and descending
towards the tail. The oral veil is bilobed, and bears on either side five processes, some
simple and some branched. This veil is continued laterally as a not very prominent
pallial ridge, bearing numerous small papillae, the last of which on either side is bifid.
Similar papillae are scattered over the sides of the body where they are arranged in two
irregular rows, over the dorsal surface, and over the tail, where (to judge from the drawing)
they are united and form a sort of ridge. The oral tentacles are short and tubercular.
The rhinophores are perfoliate and retractile within short sheaths. The gills are three
in number and tripinnate. The colour is white, but the rhinophores, branchiae, and the
tips of all the processes are light yellow.
Alder and Hancock’s specimens are unfortunately not forthcoming, but a preparation
of the radula1 has been preserved. It consists of about forty rows. There is no central
tooth. The first lateral (which is often hidden by the second and was apparently not
seen by Alder and Hancock) is rather small and bears only a rudimentary hook. The
second is of the large falcate type found in Plocamopherus, Polycera, etc., with a spur on
the base which projects into the rhachis over the first lateral. The third to the seventh
teeth are less distinctly hamate, but rise up into a more or less pointed projection which
becomes longer and longer, until the eleventh, which is almost flagelliform but smooth.
The remaining teeth are very long, slender, and minutely denticulate. They lie in a
sheaf or bundle, so that it is difficult to count them, but there must be at least twenty to
thirty.
The printed descriptions do not state whether there is any labial armature or not.
1 The teeth in Fig. 5 are drawn from this preparation.
CRIMORA PAPILLATA. I l l
But I have found a rough drawing of the radula by Hancock on which he has written
“ No jaws, no collar in second spec, examined in 1865.” No generic or specific name
is written on the paper, but the radula is unmistakable, and the specimen mentioned is
no doubt the one which Alder (l. c.) says was found by Mr. Norman in 1865. I t may
therefore I think be concluded that the labial cuticle is not provided with jaws or other
armature, and that Crimora is probably allied to Triopa, which has the same peculiarity.
The use of the long external teeth is not known. Something similar may be seen in the
radulae of the Rhipidoglossa and of Bostanga pulchra and li. muscula among Dorids.
There is no information as to the genitalia of Grimora.
PLEUKOPHYLLIDIA LOVENI Bergh.
B (P la te VIII, figs. 8—10.)
Bergh 4, p. 29; id. 15, pp. 77—86. Alder 1, pp. 17—18.
This species is not uncommon on the British coasts. I have examined several
specimens from both Plymouth and Lowestoft. The living animals are from 30 mm. to
40 mm. long. The dorsal surface is of a rather bright brick red, marked with a varying
number (twenty to fifty) of longitudinal white lines, some of which are broader and
plainer than the others. The rhinophores and the edge of the tentacular shield are
whitish; the rest of the shield is reddish. The branchiae and side lamellae are yellowish.
The foot is white with a reddish tinge. The branchiae are thin and about twenty; the
side lamellae very thick and about thirty. In front of the rhinophores is a low broad
prominence (the caruncle). When the animal is alive this prominence is not easy to
see, but it is not small and bears several indentations on its upper surface.
The jaws bear from five to seven rows of denticles. The radula consists of from
twenty-five to thirty-five rows with a formula of from 30.1.30 to 35.1.35. The median
tooth is fairly broad and bears about seven denticles on either side of the central cusp.
The first lateral is rather lower and broader than the others. The teeth in the inner
third or so of the row (the first eleven in one specimen, the first thirteen in another) are
denticulate and bear a varying number of denticulations which does not exceed seven and
sinks to two or three after the sixth tooth. In the rest of the row (after the eleventh
tooth or so) the teeth are smooth.
It would appear that the Pleurophyllidia found on the British coast is this species
and not PI. undulata (lineata) as it is sometimes called. I t differs from PI. undulata in
its colour, in having fewer and thicker side lamellae, and in its dentition. In PI. undulata
the central tooth is much broader, and all the teeth, with the exception of the last two or
three in each row, are denticulate.