Art. LI.—On a New Species of Ophiuroidea.

By H. Farquhar.

Communicated by the Secretary.

[Read before the Wellington Philosophical Society, 20th March, 1900.]

Ophiocreas constrictus, n. sp.

Disc thick, strongly constricted in the interbrachial spaces, concave in the middle, with large, long, prominent radial shields, almost meeting their whole length, and not quite reaching the centre. Diameter of the disc, 22 mm.; length of arm, 470 mm.; height of arm near the disc, 6.5 mm.; width, 7 mm. Disc and arms covered with loose, thick, wrinkled skin, especially wrinkled at the centre of the disc. Skin smooth to the eye, but under the microscope seen to be covered with exceedingly minute papillæ and numerous scattered pores or small pits on the disc and the arms near the disc. The long arms taper gradually to very fine extremities; they are rounded above and flat below. Ribs indistinct. The first two arm-pores have no scales; those beyond have two (rarely three) spiniform, bluntly pointed scales, encased in skin, with rough tips; towards the base of the arms they are rather stout and about equal in size, beyond the inner one is somewhat larger than the outer. The lowermost tooth is stout and bluntly pointed, those above somewhat larger and flattened.

Colour in alcohol reddish-brown above, yellowish below.

This species may be readily distinguished from the other known forms by its very long arms and the small pits in the skin on the disc and arms.

The type specimen which was collected by Mr. W. Docherty at Dusky Sound, and placed in my hands by Dr. Benham for identification, is in the Otago Museum. A dry specimen with its arms coiled around a gorgonian, found by the late Mr. T. Kirk at Jackson Bay, is in the Colonial Museum, Wellington. This is the only species of the family Astrophytidæ which has been found in New Zealand waters.