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Show 158 MR. F. E. BEDDARD O N W O R M S [Feb. 16, such as I have described in other species of Perichceta'. They appear, however (Plate X. fig. 1), to arise rather from the dorsal vessel than from the septum ; each gland is somewhat pear-shaped, with a narrow stalk which approaches that of its fellow. The sperm-sacs are in segments xi., xii. The atria are very extensive ; the glandular part occupies segments xvi.-xxi. inclusive ; the muscular duct opens directly on to the exterior and is unprovided with a thin-walled sac. The segments xvii., xviii., and xix. are masses of white glands which are no doubt connected with the papillae already spoken of. The ovaries (which are, as usual, attached to the front wall of segment xiii.) are very large and bunchy. The spermathecce are present to the number of four pairs, and lie in segments vi., vii., viii., and ix.; they open at the anterior boundary of these segments and are very dorsal in position, the external apertures being about 6 m m . from the nerve-cord. The pouch has the usual shape; the diverticulum is half again as long as the pouch. The characters of the papilla? appear to distinguish this species from all other Perichcetce with four pairs of spermathecae. It comes nearest to P. modiglianii. The above description refers to a single specimen which I shall keep as the type of the species. Since the description was written I have received a large number of other examples, all living, from Trinidad and Jamaica, and from Lagos on the W . African coast; the specimens from Trinidad I owe to the kindness of Mr. Hart, Superintendent of the Botanical Gardens ; the other specimens came from Kew. I kept a number of them alive for some weeks in the hope that they might possibly produce cocoons ; unfortunately they died without producing any. One of these specimens (which I have also kept) is illustrated in the accompanying coloured drawing (Plate IX. fig. 2). The examination of a large number of individuals has shown that the characters of the genital papillae as described above are not quite distinctive of the species. In a good many individuals the papillae were precisely as I have described them, but in others there were only a single pair present, that pair lying behind the male pores. These individuals therefore bear a very close resemblance to Perichceta sinensis. If one had only alcoholic specimens to examine and were not allowed to dissect them, it would indeed be impossible to distinguish the species by any at all marked characters. The colour, however (cf. figs. 2 & 3, Plate IX.), is here quite distinctive of the species. PERICHCETA SINENSIS, n. sp. Of this species of Perichceta I received a number of living specimens from Kew Gardens; they came from Foochow in China. A coloured drawing which I exhibit (Plate IX. fig. 3) was made by Mr. Smit from the living worm. I ought to mention, however, that that 1 P. Z. S. loc. cit. |