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Show 648 SIR C. ELIOT ON NUDIBRANCHS [June 19, D. tuberculata" and under D. pardalis, the species described next, " Tongue as in the last species, with the addition of a prehensile collar." The animal obtained by the ‘ Siboga' should perhaps be known as Disc, berghi. P l a tyd o r is p a p il l a t a E lio t. % -Hoplodoris desmoparypha B. var. (Eliot, Proc. Zool. Soc. 1903, ii. pp. 379-380. Bergh, in Semper's Reisen, Suppl.-Heft i. p. 51 ; Siboga, p. 113.) In making an examination of further specimens of this animal, I have found a spine in the accessory gland attached to the female genitalia. The structure of the gland seems to be as described by Bergh for Hoplodoris, but the spine is straighter. I cannot help thinking that the species is Hoplodoris desmoparypha, or at least very closely allied to i t ; but I have not been able to find a labial armature as described by Bergh. In one specimen there seemed to be something like a plate or girdle on the labial cuticle, but it was formed of fibres or filaments and not of the rods found in Discodoris and other genera. As a labial armature is generally unmistakable and easily found, I do not think its presence can have been overlooked. On the other hand, it is often developed in very different degrees in different individuals of the same species, and may perhaps disappear. In his first description (S. R. 1. c. p. 53, note) Bergh seems to imply that it was vestigial or imperfectly preserved. In my specimens the buccal cavity is black or brown. The teeth are as previously described by me {I. c.), but the outermost are sometimes slightly and irregularly serrulate *. The formula of the radula is about 40 x 80.0.80. There is a large sausageshaped prostate. The external characteristics correspond in most respects with the descriptions of Hop. desmoparypha, but the dorsal papillae are far more developed and sometimes become branched processes 5 mm. long ; but there is much variety in this respect, as also in colour. The spots and borders on the under side are particularly variable. The gill-pocket is sometimes distinctly stellate, and sometimes merely irregularly jagged or undulated. The tentacles are in all specimens large but flat. The anterior margin of the foot is deeply grooved and notched, and the upper lamina overhangs the lower. The animal has been observed to bury itself in sand, and the dorsal papillae resemble bits of sand when it is alive. It may be doubted whether Hoplodoris is best regarded as a separate genus or a section of Platydoris. Most of the characters agree with that genus, and I do not think that the presence of either an accessory gland and spine or of a labial armature * Proc. Zool. Soc. 1903, ii. p. 379, fourth line from the bottom: " innermost " is a misprint for " outermost." |