SECTION STAURODORIS.
DORIS VERRUCOSA Cov.
Bergh 38, pp. 578—583. Vayssiere 2, pp. 18—28.1 Cuenot 1, pp. 10—17.
This form is common in the Mediterranean (Marseilles, Naples, and Trieste) and on
the Atlantic coast of France (Arcachon). I t attains a length of as mucli as seven centimetres,
but more usually of four or five. The coloration is variously described by the
naturalists who have seen the living animal. In most cases the ground colour is yellowish,
varying from yellowish-grey to rich orange, but there is also often a bluish tinge, found
as a patcli in the centre of the back or on the tubercles. The Mediterranean specimens
are even described as being of a bluish-violet, but in the Atlantic specimens yellow seems
to predominate. The back is studded with both large and small tubercles, of which the
larger are generally erect, clavate, and rounded. There are usually three or four tall
tubercles round the orifice of each rhinophore, and the branchial pocket bears a circlet of
prominences, which often take the form of large and small tubercles set alternately.
The branchiae vary from ten to eighteen in number. Typically they are pinnate, but not
infrequently they are bifid or trifid, and more rarely divided into several branches.
D. verrucosa shows considerable variation in (a) colour, (b) the number and
division of the branchiae, (c) the arrangement and shape of the tubercles. In some
specimens the tubercles are connected by rudimentary ridges. The radula also shows
great variation in breadth, ranging from 45.0.45 to 100.0.100. Vayssiere states that two
brownish spots in the buccal cavity represent traces of jaws.
D. verrucosa is recorded as occurring sporadically in the British marine area. Mr.
Gr. P. Farran found one specimen at Fahy Bar, Ballynakill, West Ireland (Ann. Rep.
Fish. Ireland, 1902—3, part ii, app. vii, 1905, pp. 207—208). Bergh (System der
Nudibranchiaten Gasteropoden) unites it with Staurodoris januarii, St. ocelligera, and
St. pseudoverrucosa,3 and including these varieties the species is now recorded from the
Mediterranean and Adriatic, the coast of Brazil, the Atlantic coast of Europe, and South
Carolina. I have not myself seen the living animal in British waters, but I have
examined three specimens described as coming from the Firth of Clyde and Salcombe.
Two specimens from the former locality were courteously placed at my disposal by
the Museum of the Manchester University. The larger is 35 mm. long and 21 mm.
broad; the other slightly smaller. The details given below refer to the larger specimen,
unless otherwise stated.
Both specimens are depressed, rather stiff and hard, uniform whitish-yellow in colour.
The back is studded with large and small tubercles. There are fifteen of the former,
about 3 mm. high and 2 mm. broad. Smaller ones are scattered among them, and the
1 Vayssiere appears to have in some cases transposed the names Stau/rodoris verrucosa and
Archidoris tuberculata, v. Cuenot l. c., pp. 15—16.
2 Gadziekiewicz’s Staurodoris bobretzkii, from Sebastopol; Fischer’s Doris eubalia, D. seposita,
and D. biscayensis, all from Arcachon, are probably young varieties of D. verrucosa.
tubercles decrease in size towards the edge of the mantle, which is fairly wide. The foot
is broad; no groove or notch is visible on the anterior margin. rl he tentacles are ridgelike.
The rhinophore pockets are protected by four tubercles (two large and two small) in
the smaller specimen and by three in the other, one of the smaller tubercles not being
developed. The branchiae are simply pinnate, eighteen in the larger specimen, fourteen
in the smaller. The pocket has a, thin slightly raised lip, bearing eight tall, slender
tubercles about 3*5 mm. high, alternating fairly regularly with quite small ones.
The intestines are yellowish, except the stomach, which is black from the colour of
its contents. The spermatotheca is very large. The formula of the yellowish radula is
55 x about 60.0.60. The teeth are simply hamate, and rather crowded. The outermost
are degraded, but not denticulate. In the anterior, but not in the posterior rows, the
innermost teeth project somewhat into the rhachis, which bears longitudinal folds.
DORIS VERRUCOSA Cuv., var. MOLLIS.
One specimen, labelled “ Salcombe, R. A. Todd, 3, VIII, 1900.’ The measurements
are: length, 21 mm.; breadth, 12 mm.; height, 7 mm. The colour is white, with a faint
yellowish tinge; the texture soft. The foot is 17 mm. long and 6 mm. broad, with a
longish free tail; it has slight traces of a groove in front, but no notch. The mantle
edge is ample, and measures about 4 mm. The tentacles consist of a ridge-like prominence
on either side of the mouth; they are attached for the greater part of their
length, and show slight traces of a fold. The back is somewhat sparsely tuberculate.
Down the centre run six fairly regular longitudinal lines of large tubercles, about 1*5 mm.
wide and!;|l! mm. high. Between them and on the mantle edge are smaller tubercles.
A few tubercles near the branchiae are taller and almost clavate. There is no trace of
ridges connecting the various tubercles. The rhinophores are deeply perfoliate, and
emerge between two tubercles. The rim of the branchial pocket is slightly raised, and
bears ten tubercles of various sizes, but all quite distinct^The largest are 1 mm. high.
The branchiae are simply pinnate, the pinnae being alternately long and short. They
project about 4’5 mm. from the pocket, and lie flat on the back like a star. Seen thus
they appear to be thirteen, but on opening the pocket it is found that nine are long and
separate, and four small, springing from the sides of the longer ones. All the plumes
are united at the base in a common circular band, which bears papillas outside. The anal
papilla is central.
The intestines are white. In the central nervous system the cerebropleural ganglia
are above the pedal, which as preserved lie below them at the side. The eyes are black
and distinct.
The buccal mass is elongate. The radula is colourless, with a maximum formula of
40 x 45.0.45. The teeth are rather straight and only slightly hamate. Towards the
end of the rows the spike becomes reduced and the base increases, with the result that
the tooth resembles a broad, clumsy hook. The two innermost teeth project into the
rhachis, and are lower than the rest, but not denticulate.