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Fam. 1, Plate 5.
DORIS JOHNSTON! Alder and Hancock.
D. flavescens, interdum maculis fuscis: pallio granulis minutis confertis : branchiis 15, tripinnatis,
anum forma calicis cingentibus, intra foramen retractilibus: tentaculis brevibus, crassis, fusco-maculatis.
Doris obvelata, Johns, in Ann. Nat. Hist. vol. 1, p. 52.
Hab. Among rocks near low-water mark. Berwick Bay, Cullercoats, and Newbiggin, Northumberland.
Rothesay, Isle of Bute. Skerries, off the Dublin Coast, G. C. Hyndman, Esq. Scarborough,
J. S. Bowerbank, Esq. Torbay.
Body an inch and a half or two inches long, ovate when at rest, but capable of great
extension, rather convex on the back and depressed towards the sides, generally yellowish
white or pale cream-coloured, occasionally of a huffish orange or lemon yellow. Cloak ample,
closely covered with very minute, equal, linear, and spiculose tubercles, scarcely visible to
the naked eye, and giving the cloak a granular appearance. It is blotched with pale
brownish patches, and sometimes with a few small dark chocolate-brown or blackish spots,
arranged in two or three longitudinal rows. The under side is smooth or very slightly
granulated. Dorsal tentacles short, broad, and much rounded above, the apex projecting in
a small nipple-like point; lamellated with 10 to 15 close-set plates, and covered with
numerous dark brown spots; without sheaths, but having the margins of the cavity slightly
raised and minutely tuberculated. Branchial plumes 15, tripinnate, yellowish white or
sometimes pure white, encircling the brown tubular anus, and forming a beautiful blossom-like
cup. They are retractile within a single cavity, the margin of which, when the plumes are
extended, rises into a distinct rim; the plumes issuing from this? when viewed in profile,
have a peculiarly elegant appearance. Mouth slightly proboscidiform, with two long,
linear oral tentacles. Foot elliptical, yellowish, deeply grooved in front, the upper portion
divided into two lobes below the mouth. It projects a little behind the cloak when the animal
is in progression.
This species appears to be pretty generally diffused on our coasts, but nowhere common.
It may, however, have been sometimes overlooked in consequence of its general resemblance,
on a superficial view, to D. tuberculata. It was first described by Dr. Johnston from a small
specimen found by one of the authors of this work while exploring with him the rocks in
Berwick Bay. Dr. Johnston referred it to D. obvelata of Muller; but as we cannot agree
with our friend in this opinion, we gladly dedicate the species to its talented describer, to
whom we attribute the impulse that first led our studies in this direction. Muller describes
his Doris obvelata to be covered with unequal convex papillae, and the cloak veined beneath;
the branchiae he calls a confused serrated lobe, and the oral tentacles auriform lobes. Now
in this species the tubercles are equal, nearly linear, close, and much smaller than those of