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Show 94 ZOOLOGICAL COLLECTIONS MADE DURING [Jan. 4, to differences in modes of preservation, or to be such as come within the range of individual variations. ASTERIAS NEGLECTA, sp. n. (Plate IX. fig. 4.) The species now to be described is represented by a specimen which was brought home by Dr. Cunningham, and which has as yet remained undescribed. It resembles A. meridionals in having a groove between the spines of the actinal and abactinal surfaces, in which the papular spaces are largely developed ; but it is more closely similar to A. brandti in the characters of its abactinal surface, for granules are developed on the spine-bearing plates. Arms five, elongated, and tapering gradually ; the adambulacral spines are arranged in two rows, are cylindrical in form, and are about 2 millims. long at the middle of the arm ; on either side of these there are three or four irregular longitudinal rows of short spines. The plates on the abactinal surface are richly covered with granules; these are closely set, are irregular in shape, and are each provided with a single short spine, which is hardly lighter in colour than the brown plate itself; the disks are somewhat irregularly arranged in six rows; and occasionally there are two spines on one disk. At the side of the arm and above the already mentioned groove there is a row of spines : these are set singly at the base of the arm; but tbey rapidly become double, and occasionally a third spine appears. The deeply set madreporic plate is placed quite at the edge of the central disk, on which the spine-bearing plates frequently have two or even three spines developed. 22=83 ; r = 1 2 ; or the greater radius is about seven times the less. Greatest breadth of arm 19"5 millims. One specimen, Gregory Bay. Coll. Cunningham 1. LABIDIASTER, Liitken, 1871 (Vidensk. Medd. 1871, p. 289). I have no hesitation in placing the specimen now to be described in this genus; the only point in which it does not satisfy the definition of Dr. Liitken is in the number of its arms. The learned naturalist who defined this genus says "brachia numerosa, triginta vel pluria." The species now to be described has in all only twenty-six arms'2; but I cannot think that this difference is, at the utmost, anv more than a very poor specific character. The size of the specimen collected by Dr. Cunningham is rather less than half that of the one described by Liitken. If it is a different species from that form, the specific characters are not as yet sufficiently well marked to enable us to define it as such. I look upon it as a young specimen of L. radiosus, Liitken ; if it shall turn out to be distinct, 1 I subjoin a list of the other species from this region which are represented by specimens in the national collection:- A. sulcifera, Perrier. Cape St. Vincent, Fuegia. A. rugispina, Stimpson. Gregory Bay. A. perrieri, Smith. Kerguelen. A. meridionalis, Perrier. Kerguelen. A. antarctica, Liitken. a So Studer found a specimen with 29 arms (MB. Akad. Berl. 1876, p. 457). |