As the philosophical study of these animals is yet in a state of progression, and has
lately received much attention from physiologists, the authors have also determined to defer
their general views on the Order till near the completion of the work, so that they may be
brought up to the knowledge then attained.
In the meantime they have given a Synopsis of the genera into which the British species
may be divided, with a list of the species at present known. This will allow the reader at
once to refer each species, as it appears, to its proper place, and to understand the characters
of those genera, the detailed account of which may not appear until a subsequent part
of the work. This synopsis will afterwards be superseded by a more complete systematic
arrangement.
The authors have pleasure in stating that, in making out the anatomical details, they
have had the able assistance of their friend Dr. Den is E mbleton, Lecturer on Anatomy in
the Newcastle School of Medicine. The plates are accurate transcripts of their original
drawings. They have been executed by Mrs. H olmes, an accomplished artist in Lithotint,
an invention of Mr. H ullmandel, admirably adapted for pourtraying the delicacy and
beauty of these fragile inhabitants of the sea.
Newcastle; June 1845.
BRITISH NUDIBRANCHIATE MOLLUSCA.
S Y N O P S I S .
Sub-Kingdom. Mollusca.
Class. Gasteropoda.
Order. N udibranchiata.
Pam 1, DorididjE. Branchial plumes surrounding the vent on the medio-dorsal line.
Sub-Family, Doridirue. With a cloak.
Gen. 1. Doris, Linnaeus. Tentacles clavate or conical, retractile within cavities, sometimes slightly
sheathed: cloak large, covering the head and foot \ without appendages.
*Body depressed: plumes retractile within a single cavity.
D. tuberculata, Cuv.
D. flammea, A. & H.
D. Johnstoni, A. & H. (D. obvelata, Johns.)
D. coccinea, For.
D. repanda, A. & H.
D. mera, A. & H.
**Body depressed: plumes retractile within separate cavities.
D. Ulidiana, Thomp.
D. muricata, Mull.
D. aspera, A. & H.
D. bilamellata, Linn.
D. affinis, Thomp.
D. depressa, A. & H.
***Body convex; plumes non-retractile.
D. pilosa, Mull.
D. similis, A. & H.
D. laevis, Mull.
D. subkevis, Thomp.
Gen. 2. Goniodoris, Forbes. Tentacles clavate, non-retractile, without sheaths: cloak small, exposing
the head and foot: without appendages.
G. nodosa, Mont.
vars. G. Barvicensis, Johns.
G. marginata, Mont.
G. emarginata, For.
G. elongata, Thomp.