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Show 408 PROF. F. JEFFREY BELL ON THE [May 1, Dr. Liitken's view is expressed thus J :-" One has some help in this difficult work from colour-markings, but it is not to be understood that all individuals of the same species present the same colour, or have quite the same design (Tegning); but as a rule one will find that every species has its characteristic pattern or system, in the details of which it rarely makes exceptions." While much of this is true, it is on the other hand perfectly certain that any one who attempts to name species of Ophiothrix with colour or pattern as his guide will soon find he can make very little way. I can, indeed, only repeat and enforce what I said in 18842 on this point. Eor example, Ophiothrix martensi was said by its describer, Lyman, to be bright indigo on the dorsal surface of the disc, but there is in the present collection a specimen which is light green. The identification of specimens of Ophiothrix is such a difficult matter that it is unnecessary to express the hope that other workers will imitate m y reserve. The difficulty is to get any one to work at the genus at all! OPHIOPTERON ELEGANS. Ophiopteron elegans, Ludwig, Zeitschr. f. wiss. Zool. xlvii. (1888) p. 459. Mr. Bassett-Smith is to be warmly congratulated on taking examples of this species, which is known only from the single well-preserved and the one ill-preserved specimen brought to Europe by the late Dr. J. Brock, and fully described by Prof. Ludwig in 1888. 1 have made a careful examination of the seven specimens in the present collection, and have nothing material to add to Prof. Ludwig's account. I notice, however, a pinkish hue on the dorsal surface of the arms. The examples were taken at various depths between 23 and 47 fathoms. The most remarkable and interesting find of Mr. Bassett-Smith when on the 'Egeria' was an Ophiurid, of which it is difficult to exactly assign the systematic position. Description of the Specimen.-With the general appearance of a young Astrophyton (see Plate XXVII.), the joints of the arms are distinctly marked off from one another by brown lines ; the joints of the more distal branches are slightly coiled on themselves, but the more proximal trunks and branches appear to be quite stiff. The disc is covered above and below by a number of plates ; there are teeth and mouth-papillae; the bursal clefts are small and on the side of the arm, or in the same position as in Trichaster or Astrophyton. The surface of the arms is coarsely granular, and there are spiny hooks at the side of the arm; so that there is so far no essential difference from the typical Astrophytid structure. 1 Tom. cit. p. 51. a Report .... Voyage H.M.S. ' Alert' (London, 1881). See particularly pp. 117, 141 & 142. |