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Show 72 PROF. F. J. BELL ON THE [Feb. 19, continua tuberculorum similium 7-9, versus apices brachiorum descrescentium, carinas brachiorum coronat; minora 1-3 in lateribus brachiorum series duplices utrinque formant; ad angulos stella? vulgo nulla; tesselce ventrales propria sat magna?, se-junctee, granula majuscula, tuberculis hand intermixta, gerunt; pedicellaria; lineares elongates in vicinis ambulacrorum, rariores in dorsualibus tuberculis destitutes, conspiciuntur; papilla ambulacrales interna 7, externee 2 (rarius 1 v. 3), complanata?; orales series duplices formant, infernas 12, externas 5 numerates. Hab. ad oras insulae indicae Billiton (specimen junior ?)." OREASTER LINCKI. Asterias lincki, De Bl. Diet. Sci. Nat. Ix. p. 219. Pentaceros muricatus, Perrier, Rev. Stel. p. 239 \ R = 3 r. Disk moderately high ; arm moderately wide, not at all acutely pointed. Lophial spines well developed, the apical very prominent; a spine or two sometimes developed within the apical region. About 18 marginal plates; the superomarginals alone form the sides of the arms, and are alone provided with spines ; these are confined to the distal end, and vary considerably ; from one to four may be developed, and in some specimens they are twice as long as they are in others. Adambulacral spinulation diplacanthid ; in the inner row eight poorly developed spines, in the outer two, which are much stouter, for each plate; the tips of the latter are often marked by several shallow grooves ; as so frequently happens, a forcipiform pedicellaria is developed between each inner group of adambulacral spines. The separate ventral ossicles are hardly, if at all, to be made out under the exceedingly coarse granulation by which they are covered ; the separate granules vary considerably in size, and a few valvular pedicellariae are scattered among them. The granules on the marginal plates are hardly less coarse. The dorsal surface is rendered markedly reticulate by the great size and close approximation of the poriferous areas, two of which pass along each side of every arm ; in the middle of the arm the second of these may equal in length as much as half the whole height of the arm ; sometimes the connecting processes of the ossicles become very delicate, when the whole side of the arm appears to form a huge poriferous area. Spines are very irregularly developed at the angle of the areas; sometimes they are distributed so regularly that one may almost speak of a regular row of spines running on either side of the lophial series ; in other cases they are completely absent. This happens sometimes also to the spines of the lophial ridge itself, hut they are ordinarily very well developed, as are, too, the apical spines and the spines that stand below them on the sloping sides of the disk. The granulation on the dorsal spines and ossicles is very coarse and extends sometimes quite 1 M. Perrier here adopts the name of Linck ; a course in which, I regret, I cannot follow him. |