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Show 1881.] PROF. F. J. BELL ON THE GENUS ASTERIAS. 515 Colour of the single specimen yellowish white, the suckers rather darker. Presented in 1873, by Dr. Gwyn Jeffreys ; collected by Capt. H. C. St. John, R.N., in the Japanese seas. ASTERIAS JAPONICA, Stimpson. (Plate XLVIII. figs. 6, 6a, 6b.) As the description of this species, if ever published, must be very difficult of access, and as it seems to be unknown to the bibliographers, I add the following notes, which will, I hope, enable students to recognize it when they find it. I know of its existence only from the presence in the British-Museum collection of a dried specimen presented in 1861 by the Smithsonian Institution, and bearing their label " Asterias japonica, Stm., I. of Jesso." General formula 2atc. Arms five, elongated, narrow, disk small; adambulacral spines in two rows ; madreporic plate small, rather obscure, anechinoplacid, close to the edge of the disk ; both the abactinal and actinal surfaces are rough with short slender spines, closely packed. The spines in the row just outside the adambulacrals are blunter than any of the rest; their free end is broader than their base; the spines of the next row are also rather blunt; beyond this there are two rows of more slender spines; and beyond this fourth row there is a well-marked line, in which lie the respiratory pores. The spines which extend beyond this over the whole surface of the arm, and form something like six rows on either side of its middle line, may be set singly or in small clumps ; they are all short, slender, and rather sharp, and are richly provided with pedicellariae. Respiratory pores occupy the interspaces on the surface of the arm. A distinct median dorsal line is apparent on some, though not on all, of the arms of the specimen under description. 22 = 55, /-=7'5. Breadth of arms at base 10 millim., close to tip 3 millim. Colour of dried specimen umber-brown ; the dried ambulacral suckers black. EXPLANATION OF THE PLATES. PLATE XLVII. Fig. 1. Asterias philippii, n. sp., abactinal surface, nat. size. 1 a. Actinal surface, nat. size. 2. A. inermis, n. sp., general view, nat. size. 2 a. Actinal surface of ray, X1^. 3. A. verrilli, n. sp., general view of actinal surface. 3 a. Part of abactinal surface, X 2. PLATE XLVIII. 4. A. spirabilis, n. sp., actinal surface of ray, Xii. 5. A. rollestoni, n. sp., actinal surface, X 2 . 5 a. A. rollestoni, abactinal surface, X2. 6. A. japonica, Stm., abactinal surface, Xlj. 6 a. A. japonica, actinal surface, xl£. 6 b. A. japonica ; some of the spines of the abactinal surface, further magnified. |