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Show 290 MR. F. P. BEDFORD ON MALAYAN ECHINODERMS. [Mar. 20, superomargiDals meet across the abactinal surface, but the actinal plates are unaffected. Tbe anus is central, without any tendency towards Cuenot's interradius E C in any of the five specimens brought back: Prof. Ludwig, in his definition of the genus Archaster, says, " After central" (loc. cit. p. 667); whereas in the body of the work (p. 5S7) he corroborates Cuenot by stating that it lies " stets mehr oder weniger excentrisch in der Richtung einer interradialen Hauptebene," and he then continues to describe the particular interradius in agreement with Cuenot's notation BC, although he adopts a somewhat different mode of orientation. Measurements of two extreme individuals :- No. of Arm-marginals. 7?. r. breadth. 46 64 12 13 46 71 10 13 2. CRASPIDASTEH GLAUCONOTUS, sp. nov. (Plate XXIV. figs. 8 a, b.) References. W . P. Sladen,' Challenger ' Reports, xxx. Asteroidea, 1889. H. Ludwig, Bronn's Thier-Reich, Bd. ii. Abth. 3, Buch 2, 1899. A. E. Verrill, Trans. Connect. Ac. vol. x. pt. 1, 1889, p. 213. R= 5 X r. Locality. Several specimens from 1 to 3 fathoms, Malacca. Marginal plates very robust, superomarginals devoid of spines, granular; inferomarginals also granular with a variable number of spinelets ; in some specimens there are two complete rows of 3 to 5 spinelets in each row on each plate, the abactinal ones being larger than the rest, but not standing out as a conspicuous fringe as they do in most Astropecten ; in other specimens fewer spines are developed, in a few cases only one or two extra spinelets occurring in addition to those on the lateral line ; the ventrolaterals also carry each several spinelets; as in Craspidaster hesperus, the ventrolaterals are few in number, not extending beyond the fourth inferomarginal. The abactinal surface is paxillose, each paxillus having a circular crown of about eight papilla?, the centre being usually smooth; as in C. hesperus, the plates are covered with a membrane which forms a serrated fringe on the edges of the marginals and dorsoventrals ; superambulacrals are present between the ambulaerals and inferomarginals; the tube-feet are conical, without any sucking-disc; adambulacral armature is diplacanthid, arching over the furrow is a comb of six subequal spines, outside this on the aboral part of the ventral surface is a single rather stout spine, and on each of the three remaining edges of each plate is a vertical row of 3 to 5 rather short spines. Madreporite is small and circular, situated about halfway from outer edge to centre. In the youngest specimen obtained the spiculation of the ventrolaterals is already developed. |