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Show 1894.] ECHINODERMS OF MACCLESFIELD BANK. 393 In fact I have had forced on me the conviction that Macclesfield Bank is a nursery ; with a rim submerged 9 fathoms * beneath the surface any pelagic larvae that will can enter within its boundary; being 76 miles long and 36 miles broad, it affords some opportunities for the larvae to settle, and the average depth within the rim is from 40 to 50 fathoms. I may therefore suggest that it is of great importance that as full collections as possible should always be made in areas resembling the inside of this reef, for not only are questions of synonymy to be by this means settled, but the more interesting study of the changes that occur during growth can only be carried on with extensive series, the relationships of species can be more satisfactorily considered, and material be brought together of immense value to the morphologist. It would be quite possible so to arrange the material for this paper as to make it of intolerable length, but I think I can so dispose of it as to bring all I have to say within reasonable compass. I propose to give three lists :-(A) of the species from N.W. Australia; (B) of those from the Arafura andBanda Seas; and (C) of those from the Macclesfield Bank, in all of which the observed range in depth will be duly noted; after each species I place the name of the author who first described it. After these lists I give notes aud descriptions in systematic order. The point of greatest interest is the discovery that the sygygial joints at the bases of the arms of Comatulids by no means exhibit the regularity which is ordinarily believed to be one of their chief characteristics and their best claim to be used as aids and guides to tbe grouping of the species-that is to say, they have been taken as being very much more valuable than mere specific characters. Antedon bassett-smithi (see p. 399) shows how the syzygies may vary in one individual specimen; while the broken and nameless Actinometra (see p. 402) is positively appalling to a student of Comatulids, for it has no syzygy on either second or third brachial. Where there is no large series it is very difficult to speak with any confidence as to the significance of unexpected irregularities, which may, of course, be merely individual, but, in systematic zoology, we have to beware always of the influence of generalizations based on material which is always becoming proportionately smaller. The general acceptation of Dr. P. H. Carpenter's classification removes the " idol" from the category of " idola specus " to that of " idola fori"; but we must not only remember, we must always keep before ourselves the doctrine of Macleay that " no character is natural until it has been proved to be so."2 This is, of course, saying in as many words that there is no 1 See Bassett-Smith, Ann. & Mag. Nat. Hist. vi. (1890) p. 356. 2 See J. D. Macdonald in Trans. Linn. Soc. xsiii. p. 75. Pupils of the late Prof. Rolleston need not be told whence I derived my knowledge of this |