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Show 1904.] FROM EAST AFRICA AND ZANZIBAR. 389 outer side. The second and third are much like the innermost, but are denticulate on the outer side only. The rest are simply hamate, of the ordinary shape, and bear about 10 minute denticles. The outermost are, as usual, irregular, and the denticulations are mainly on the apex. 4. CHROMODORIS ANNULATA. (Plate XXIV. figs. 1-3.) Chromodoris annulata, Eliot, Abstr. P. Z. S. 1904, No. 4, p. 15, March 8. Many specimens found among Zostera off the mouth of the Creek at Zanzibar- and other places at low water during springtides. The living animal (PI. X X I V . fig. 3) was very soft, with an ample undulated mantle-margin. A large specimen when in an extended condition was 55 m m . long and 15 wide, but when contracted the same individual was 45 m m . long and 25 wide. The upper surface was of a somewhat translucent white, studded with yellow spots. Round the margin was a border of deep purple, and two rings of the same colour were so placed as just to include the rhinophores anteriorly and the branchiae posteriorly within their respective areas. The underside was white, with yellow spots on the tail and the sides of the foot. The rhinophores were deep purple, and so long that they were rarely wholly retracted. The branchiae were white, with a deep purple stripe clown both the inner and outer edge, and were kept waving from side to side. The animals were found in conspicuous positions, and made no attempt to hide themselves among the Zostera weed. By a somewhat unusual change, which deserves to be noticed as showing how preserving-fluids may alter colour, the alcoholic specimens have become of a reddish purple with white spots, the border and rings having disappeared * and apparently diffused their pigment over the whole surface. Fortunately the notes on the living animal were very full, and there appears to be no doubt that the specimens are the same despite their transformation. The body is very soft and the skin perfectly smooth. The mantle is ample, the free edge measuring 7 m m . over the head and 6 at the side in a specimen where the visceral mass is 10 m m . broad. The openings of the rhinophores and branchiae are slightly raised in some, but not in all the specimens, and vary in size. They are no doubt capable of contraction and expansion in life. The branchiae (PI. X X I V . fig. 2) vary in number from 9 to 16 according as an inner row is present or not, but on an average the smaller number is more frequent in this species than in Chr. reticulata, sykesi, and cctvce. The foot is narrow and rounded, grooved in front but not notched. Two small folds pass upwards from the foot, uniting it with the sides of the head and with the mantle. The tentacles are small and placed at the lower angles of the mouth. The labial * [Their durk purple-blue became almost at once a light red, which disappeared gradually.-C. C.J 2 6* |
