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Show 1894.] ECHINODERMS OF MACCLESFIELD BANK. 401 low centrodorsal bare of cirrus-sockets. The first syzygy is on the third brachial, the next on or about the thirteenth. The most proximal brachials are square, those that succeed them are triangular. The second pinnule is very long and stiff, much longer than the first or third. Arms purplish, with yellowish dots and patches; the cirri yellowish at base and purplish at tip. Spread 120 mm.; diameter of disc 6 m m. Macclesfield Bank, 13 fms. ANTEDON MOOREI, sp. nov. This species is probably most nearly allied to A. compressa, P. H . C , but it has only faint spinous processes on the cirrus-joints. Cirri 25 to 30, with 25 joints. Centrodorsal bare in the middle. No syzygies on radials, distichals, or palmars. There may be post-palmars. The third brachial syzygial; arm-joints iii.-vi. squarish, the succeeding triangular, and the more distal gradually overlapping. Colour purplish, with the free ends of the arms white. Macclesfield Bank, 13 fms. The single specimen is a good deal broken, but it is interesting as belonging to a series of the group of which Dr. Carpenter knew only one type. ANTEDON FIELDI, sp. nov. Allied to A. moorei, but distinguished from it by the broad spiue on the cirrus-joints. Cirri about 20, with 18 joints, almost completely covering the centrodorsal. No syzygy on radials or distichals ; the first on the third brachial. Colour bright purple with lighter cirri. Macclesfield Bank, 22-30 fms. I offer a brief diagnosis of this species, as the peculiarity of the broad spines on the cirrus-joints ought to be known. I associate with these two species the names of the commanding officers of H.M. ships 'Peuguin' and 'Egeria,' Captain W . U. Moore, E.N., and Commander A. M . Eield, E.N. There is yet another bidistichate species, which is altogether too much broken for description (13 fms., Macclesfield Bank), which has about 30 cirri and 20 smooth cirrus-joints. There are distinct signs that a re-arrangement oi the useful key given by Carpenter of the " Spinifera-group " will soon be needed. Considering the lar^e number of new species assignable to this group found by Mr. Bassett-Smith, I cannot but wonder that none were found by the'lamented Dr. Brock in his expedition to Amboina, the neighbouring region. I do not know what led Dr. C. Hartlaub to say of the group that it " umfasst . . . Pormen, die in Wesentlichen dem Caraibischen Meere angehoren " \ but it was not the then known facts of distribution ; still less is the statement accurate after the discoveries at Macclesfield Bank. 1 Op. cit. p. 75. |