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Show 92 ZOOLOGICAL C O L L E C T I O N S M A D E D U R I N G [Jan. 4, from those near it by small aggregations of large granules. Now in A. brandti the spines are present and the disks are present, as are, too, the granules, but the granules, instead of separating the disks, are placed upon them. The species may be thus defined :-Arms five, very long and narrow, decreasing very gradually in width ; they are largely covered with disk-like plates which are covered by large granules, with a short white spine in the centre. The adambulacral spines are in two longitudinal rows and subequal; the disk-like plates on either side are closely packed ; and their spines are much longer and stouter than those on the dorsal surface. Between these lateral rows, and extending across the arm, there are about eleven disks, which form fairly regular longitudinal rows along the arm. The exceedingly small central disk is not distinguished by any special spines; the madreporic plate is orbicular and near the margin of the disk. Spines all white. 22=86, r=7; or the greater is about twelve times the length of the lesser radius. One specimen. Trinidad Channel, 30 fms.; bottom, mud. ASTERIAS ALBA, n. sp. (Plate IX. fig. 2.) Arms five, rather stout, narrowing rather rapidly toward the end. Spines mere projections on the dorsal and lateral surfaces; adambulacral spines in two rows, delicate and closely set; these are flanked by two rows of stouter conical spines, which gradually diminish in size as they approach the distal end of the arm. External to these rows there is a bare band, which occupies the greater part of the side of the arm, and is separated from the barely convex dorsal portion by a somewhat indistinct line of short inconsiderable spines. The spines on the dorsal surface are no better developed; and the most important series is the median row of small projections. The species presents some resemblance to A. antarctica ; and this is specially well seen in the reticulated appearance produced by the mode of arrangement of the calcareous bars which make up the dermal skeleton. The disk is very small, and not provided with any longer spines than the rest of the animal. The madreporic body is of a dead white and difficult to detect. 22 = 73, r = 1 0 ; therefore R = 7'3r. One specimen. Sandy Point, 7-10 fms.; bottom, dead acorn-shells. ASTERIAS OBTUSISPINOSA, sp. n. (Plate IX. fig. 3.) This species is at once remarkable for its short blunt spines, and for the fringe of short spines which surround the madreporic body ; these are about twelve in number, while in the long-armed A. spec-tabilis of Philippi there are said to be eighteen. The adambulacral spines are arranged in two longitudinal rows, and are much less strong than the other spines; those of the inner row are the shorter. Beyond these there are three fairly regular rows of blunt spines, the innermost of which only extends about halfway along the arm. The side of the arm, bare of spines, is limited below by |