CORYPHELLA SALMONACEA (Couth).
Bergh 3, pp. 89—99; id. 24, pp. 7—8 ; id. 54, pp. 83—34.
This species is not recorded by Alder and Hancock from British waters, hut Mr.
Chas. L. Walton (who 'has kindly supplied me with the following description) reports
that the boats of the Lowestoft Marine Laboratory found it in great abundance about
lat. o5 50 N., long. 0 35' E., at a depth of 30—45 fathoms. It seems to be characterized
externally by haring large oral tentaoles and numerous small crowded cerata, which
extend to the tip of the tail, but leave a bare median space for three quarters of the length
of the back. But I have not been able to obtain a drawing of the living animal.
Measurements of a large specimen: length 20 mm.:; height 5 mm.; breadth 5 mm.;
length of tentacles 5 mm., of rhinophores 4 mm., of cerata 3'5'mm. Body firm, foot
narrow, tapering to a somewhat obtuse point at tail, and produced at the angles into
thin points. Oral tentacles broad and thi'ok, rhinophores slightly wrinkled. Eyes
small; behind rhinophores. Gerata numerous and irregular in size. The grouping
is obscure, and they continue almost to the tip of the tail. A bare space extends from
the head for about three quarters the length of the back.;;!f|The body jk semi-pellucid
white, as are also the tentacles and rhinophores; they often bear a line of opaque white
down the front. The cerata are reddish brown or fawn-coloured, with a distinct, white
ring just below the tip. The dorsal surface is tinged with reddish brown, and bears a
faint white line along the tail;: The jaws are strong and of a dark horn-colour. The
radula consists of sixteen to eighteen rows of pale yellowish-white teeth. The- central
tooth is broad with a strong median- cusp and seven to eight denticles-on either side.
The lateral teeth are slender and acute, with eight to nine small irregular denticles.
The number of denticles seems to vary considerably, and isTeported by Bergh as being
in some specimens as many as nine on the central teeth and twenty-six on the laterals.
EMBLETONIA PALLIDA A. & H.
(Plate VI, figs. 1 and 2.)
= Embletonia grayii Kent, in Proc. Zool. Soc., 1869, pp. 109-ccJll; probably alsq i
Embletonia fuscata Gould and Embletonia remigata Gould.
Alder 1, p. 86. Bergh 13, pp. 86—89. Meyer and Mobins 1, pp. 17—18.
Alder’s description of the animal is as follows; “ Body yellowish white, with a few
black spots on the back. Tentacles (rhinophores) approximating; head lobes indistinct,
forming a semicircular veil which is a little produced at the sides; branchial processes
nearly linear, set in a double longitudinal row of four or five on each side of the back.
Length 0T mm.” The number of cerata, position of the rhinophores, and shape of the oral
veil, as well as the colour, seem to make this a valid species distinct from E. pulchra and
from the dubious E. minuta. But Kent’s E. grayii, which differs from it chiefly in having
three cerata in some groups instead of two, is probably merely a variety.
Bergh has given an account of the anatomy based on specimens from Massachusetts,
which he regards as undoubtedly referable to this species. They were 2 mm. long as
preserved and had not more than two cerata in any group. : ffi:he jaws are finely denticulate.
The radula consists of about forty teeth in a single series. They are of the usual
horse-shoe shape, and bear about seven denticles on either side of the not very prominent
central cusp. Cnidocysts are present though not foimd by A. and H. in Embletonia
pulclira.
AMPHORINA QuatbefaseS.
Eliot 1, pp. 363—368.
In the paper referred to above I have discussed the relationships of Amphorina and
of the genera comprising Bergh’s family Cratenidse, and shown how small are the
differences which separate them, and how often species fail to present all the characters
of the genera to which they are referred.
Of the genera Guthona, Gratena, and Amphorina, the last may be retained provisionally,
for it will be a convenient division if many JEolids are discovered having the characters
of Amphoi'ina sensu stricto (e. g. like A. coerulea). But I can see no sufficient reason for
separating Guthona and Gratena; for the only certain characteristic which distinguishes
them is that in Guthona the head is broad, in Gratena narrow. The assertion made by
Bergh that in Guthona the auditory capsule contains a single otolith, but in Gratena
several otoconia, has been disputed. If only one genus is recognized it would seem that
the name Carolina used by Alder must be rejected from nudibranch nomenclature and
that Guthona has priority over Gratena. Alder (1, p. 43) referred to Guthona (1) G. nana,
(2) G.peachii, (3) G. stipata, (4) G. angulata, (5) G. inornata, (6) G. concinna, (7) G. olivacea,
(8) G. aurantiaca, (9) G. pustulata. Of these (4) is almost certainly a species of
AEolidiella, (5) remains somewhat doubtful, (7) and (8) are here referred to Amphorina.
The remaining species are retained as Guthona, and to them are added a few more called
Gavolina by Alder and Gratena by Bergh.
Though I retain Amphorina provisionally, I doubt if it will prove to be more than
a section of Guthona. In the typical forms it has a long tapering radula and a penial
stylet, whereas Guthona has a short radula and no armature on the genitalia. But these
characters are not constant in all forms, for Guthona amcena is said to possess a penial
stylet, and Gratena fructuosa and Gr. gymnota (which are Cuthonas according to the
nomenclature here adopted) have long tapering radulas.
AMPHORINA C(ERULEA Montagu.
(Plate YI, figs. 6—8.)
= Eolidia bassi V6rany.
Alder 1, pp. 51—52. Bergh 2, pp. 57—61; id. 13, pp. 37—39. Vayssi&re 2, pp. 60—65.
Trinchese 1, pi. xxx, xxxii, xxxiii; id. I primi momenti dell’evoluzione nei molluschi, in
R. Accad. dei Lincei, 1879—1880, p. 3; id. Protovo e globuli polari dell* Amphoi'ina coerulea.
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