Art. XXVI.—Description of a New Ophiurid.
[Read before the Wellington Philosophical Society, 12th March, 1901.]
Amphiura aster, n. sp.
A number of specimens of what I believe to be a new species of Amphiura have been placed in my hands by Mr. A. Haylock. They were found by Mr. Percy Allen at Timaru, in the sand at low water.
Diameter of the disc, 10 mm.; length of arm, about 136 mm.; width of arm near the disc, without spines, 1 mm. The disc is pentagonal, constricted in the interbrachial spaces, covered above and below with small rounded irregular scales. Near the centre of the disc the scales do not usually overlap, and around the radial shields they are larger and longer than elsewhere; below they are more regular than above. Radial shields large, long, and swollen, broader without than within, separated by a wedge of scales, meeting or almost meeting without. A pair of short, blunt, rounded mouth papillæ at the apex of the mouth-angle, and one, spiniform, tapering, and pointed, on each side. Mouth-shields rather small, shield-shaped; madreporic shield large, swollen, and oval. Side mouth-shields much broader without than within, meeting within; Arms long and slender, tapering evenly to very fine extremities. First under arm-plate small, squarish, rounded within; second and third longer than broad, and narrower than those beyond, which are squarish, with rounded angles. Side arm-plates small, with strong spine-ridges, meeting neither above nor below. Upper arm-plates oval, broader than long; the first two or three are absent in all specimens examined by me (12), except a young one, in which they are small and disconnected, evidently disappearing; sometimes those near the base of the arms are split in two longitudinally. Arm-spines subequal, somewhat flattened, six or seven near the disc, five further out, and four towards the tips of the arms. Tentacle pores very large. Two very small tentacle scales to each pore near the disc and one beyond. Colour of dried specimens pale-yellowish, sometimes tinged with red or brown; arms sometimes banded with grey.
Type specimens in the Canterbury Museum.