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Show 402 PROF. F. JEFFREY BELL ON THE [May 1, ACTINOMETRA PEREGRINA, sp. nov. This species belongs to Carpenter's series n. (torn. cit. p. 300), every known species of which, except A. cumingii (from Malacca and Queensland) and A. echinoptera (of unknown habitat), belongs to the West Indian fauna. Prom the two species just named A. peregrina may be at once distinguished by the characters of its cirri, for whereas A. echinoptera has cirri with eleven joints the new species has as many as twenty-five, while there are at least twenty-five cirri arranged in two rows, and not twelve only arranged in one as in A. cumingi. The following characters will serve to diagnose the species :- Centrodorsal moderately large and a good deal obscuring the radials; bare in its middle, with about 25 cirrus-pits, the cirri of moderate length with about 25 joints, of which the 5th and 6th seem to be distinctly the longest. The basal joints of the arms very irregular, and no two alike; the free edge of the joints soon become very finely denticulate. The first syzygy is on the third brachial, the succeeding on the eleventh and eighteenth. Pinnules remarkably well developed even at some distance from the base of the arms. Colour brownish. Macclesfield Bank, 55-60 fms. Mention also must be made of an Actinometra to which I think would be wrong to give a specific name, so broken is it, but of which it w^ould be more wrong not to say something. It will be remembered that the late Dr. H. Carpenter divided the tridistichate species of this genus into those in which there is a syzygy on the second brachial and into those that have it on the third. In the specimen now before me there is no signs of any syzygy on either the second or the third brachial. This is another very remarkable fact, and it is most important that we should obtain several specimens of this form, so as to learn whether the absence of syzygies from both second and third brachials is a constant character. If it is, it is certainly one of the most unexpected results, and taken in conjunction with what has been observed in Antedon bassett-smithi it will severely shake our faith in the value of the site of the syzygy as au aid in specific diagnosis. III. ASTEEOIDEA. ARCHASTER TYPICUS. Archaster iypicus, M . Tr. Ber. Ak. Berlin, 1840, p. 104. In two small specimens dredged, with a large example, in 23- 24 fms. of water there are no signs of any spines on the infero-marginal plates ; in a somewhat larger specimen (from 40-46 fms.) there are on some of the plates indications of the growth of spines. ARCHASTER TENUIS, sp. nov. (Plate XXV. figs. 4-6.) This seems to be a species of Archaster in the sense of |