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Show 1 9 0 6 . ] OF SOUTHERN INDIA AND CEYLON. 6 7 9 Linguella cinerea appear to have been presented by Kelaart, which is agreeable to the supposition that they represent his Diphyllidia formosa and D. marmorata. P l e u r o p h y l l id ia Formosa (Kelaart). (Plate XLII. figs. 1 1 ,1 2 . ) (Diphyllidia formosa Kelaart, 1. c. II. p. 494 ; Bergh, " Anato-niische Untersncliung der Pleurophyllidia formosa ," Verh. d. k.-k. zool.-bot. Gesellsch. in Wien, xix. 1869.) One large specimen seems to be identical with both the animal described by Kelaart and that described by Bergh. It is unfortunately very badly preserved and the body has become soft and crumbly. It is 62 mm. long and 28 broad. The shape is lingui-form. The colour is yellowish white, but the frontal shield is still faintly reddish, and the back bears traces of about 30 longitudinal stripes. The rhinophores have also preserved their pink and black coloration. The side-lamelhe are almost obliterated, but the branchiae are distinct and set in a deep cleft. There is a longitudinal furrow in the posterior part of the foot. Of the internal organs only the hard buccal parts were sufficiently well preserved to be examined. They appear to be as described by Bergh. The jaws are large, brown, convex externally, bearing on the edges many denticles which can be seen with a hand-lens. The median tooth of the radula is very broad. It bears four denticles on each side of the central cusp, which is itself slightly denticulate. The first lateral is large and bears a few irregular indentations. The next few laterals are smooth ; after that the rest are bifid, except the three or four outermost, which are again smooth. One of Kelaart's drawings represents this species lying half buried in sand with the head and tail exposed. I have seen P. californica behave in the same way, and no doubt the habit is common in the genus. The sides of the mantle are held against the body so as to form a tube, through which a current of water is sent over the gills and side-lamellse. P. formosa is allied to P. ceylanica, which has a smaller radula and the outermost teeth serrulate, and also to P. cygnea and P. natalensis, in which all the teeth are quite smooth. The figure of P. cygnea given by Basedow and Hedley (Trans. Royal Soc. of South Australia, vol. xxix. 1905, p. 149, pi. x.) is remarkably like Kelaart's drawing, and differs chiefly in representing the frontal veil as colourless, not pink. P l e u r o p h y l l id ia t^en io l a ta Berc©rli. (Bergh, Bidrag Monogr. Pleurophyllidierne, pp. 42-46. Eliot, " Nudibranchs from the Indo-Pacific," Journ. of Conch, vol. ii. no. 8, Oct. 1905.) One specimen of this fine species, which has hitherto been recorded from Mozambique and Maskat. Length if stretched |