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Show 84 SIR C. ELIOT ON NUDIBRANCHS [M^y 17, N otodoris Bergli. [Bergh, " Neue Nacktschnecken d. Siidsee," p. I l l , in Jour, d. Mus. Godeffroy, viii. 1875; Eliot, Nudibranchiata in J. S. Gardiner's Fauna and Geography of the Maldive and Laccadive Archipelagoes, vol. ii. part 1.] This genus, which is recorded from three parts of the Indo- Pacific, seems allied to sEgires and the little-known Triopella, with which it forms a small group of phanerobranchiate Dorids characterised by a hard texture, valves or other appendages protecting the gills, and undifferentiated teeth. Both jEgires and Notodoris have simple unperfoliate rhinophores. The body of Notodoris is hard and rough, often marked with prominent ridges. The frontal veil is large. The branchiae, and sometimes the rhinophores, are protected by valves. There is no labial armature, and the teeth are hamate with indications of an accessory denticle. Three species have been described, each from a single specimen-A. citrina B., N. gardineri Eliot, and the present N. minor. They are all yellow, differing chiefly in size, shape, and the form of the branchial valves. It is just possible that N. minor may be a young and undeveloped form. It is smaller than the others, and superficially resembles a Phyllidia. It has no distinct tail, no rhinophore valves, and no longitudinal ridges. The branchial valve is three-lobed and not much subdivided. Possibly the gill is constructed differently from those of other species. Both N. citrina and gardineri have rhinophorial valves and a body tapering off into a tail: the former has a single dorsal ridge running from the rhinophores to the branchial valve, which is eight-lobed : the latter has four dorsal ridges and a branchial valve three-lobed, with elaborate subdivisions. N otodoris m in o r , sp. n . (Plate III. figs. 1 a - 1 g.) One specimen from Chuaka, east coast of Zanzibar. The living animal was 13 millimetres long, 5 broad and 4 high. It was light lemon-yellow in colour, with sharply-marked transverse black lines. The flat sole occupied the whole ventx-al surface. The back was not quite smooth, the yellow parts being really low broad lumps between black depressions. The whole body was very stiff and rigid, superficially resembling a Phyllidia. The animal was never seen to move. In the preserved specimen the yellow has become whitish, but otherwise the shape and markings of the living animal are preserved. The integuments are very hard and full of spicules. There is no trace of any mantle-edge, and the body slopes straight down to the sides of the foot. Over the mouth-parts is a strong rounded frontal veil (figs. 1 a & 1 e), also descending right down to the sides of the foot, and extending laterally about as far as the rhinophores. At the beginning of the posterior third of the body are the three gill-valves (figs. 1 a -1 c). They are not noticeable except in profile, as they lie rather flat, and are not much subdivided. Beneath them lie the gills (fig. Id), which appear to |
