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Volume 15, 1882
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Genus Anthura, Leach.

(Bate's and Westwood's Brit. Sessile-eyed Crust., vol. ii., p. 157.)

Anthura affinis, sp. nov. Plate I., fig 4.

Segments of pereion subequal, cylindrical. Head somewhat shorter than the first segment of pereion. Antennæ short, not quite so long as the head; upper much smaller than the lower, consisting of four joints, of which the basal one is the largest, and a very small fifth joint bearing a small pencil of setæ; lower antennæ thick and strong, basal joint large, broad, with a groove above in which the upper antenna rests, the inner edge of this basal joint is straight and in close contact with that of the antenna on other side, along the median line; basal joint followed by three subequal joints, and a short, thick, rudimentary flagellum, the joints of which bear setæ thickly set on one side.

First pair of legs very strong, not reaching beyond the head; basos very thick distally, ischios also thick and strong, meros short, carpus subtriangular, produced along the side of the propodos, and bearing setæ on its distal extremity; propodos thick, ovate, in contact with both meros and carpus, palm short with a strong projection against which the dactylos impinges; dactylos short, strong, and curved. Remaining legs all similar, not subchelate, propodos longer than the carpus and meros together. First five segments of the pleon united so closely that the lines of suture cannot be distinguished, sixth segment distinct bearing biramous appendages; outer ramus of a single joint, half as long as the inner, semicylindrical surrounding the inner ramus, its upper inner edge serrate and fringed with long setæ very delicately plumose; inner ramus of two joints equal in length and breadth, broad, edges fringed with long setæ; telson broad, round at end, with several long setæ near the centre.

Colour—pale yellow with blotches of black on the head, segments of pereion, pleon and telson. Length about ⅓ of an inch.

Hab. Lyttelton Harbour. Found on seaweed at low tide.

This species is a true Anthura, coming apparently near to A. gracilis, from which however it is sufficiently distinct.

The first pair of legs only are chelate, all the rest are simple; they have the dactylos large and strong, the end forming a claw distinct from the basal portion; at the base of this claw three or four simple setæ arise laterally, and a short stout one on the inside. There is also a short stout seta on the inner distal angle of the propodos (pl. I., fig. 4 c and d).

The pleopoda are of the usual form, having a short basal joint bearing two equal oval plates with the distal margins setose. Each of these branchial plates is slightly constricted on each side, half way between the two

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Crustacea.

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ends. The first pair of pleopoda are modified so as to form an operculum covering the others; one of the plates, the outer I think, is long and broad so that it extends along the whole of the under side of the pleon; the inner plate appears to perform no special function, it is small and narrow, apparently becoming rudimentary (fig. 4 f). The setæ on the pleopoda are long and fringed on each side with long plumes, which are exceedingly delicate.

Cubaris rugulosus, Miers. (Cat. Stalk- and Sessile-eyed Crustacea of N.Z., p. 96.)T

This species was described by Mr. Miers from specimens in the collections of the British Museum. His specimens appear to have been imperfect, for he neither describes nor figures the antennæ. I have found it abundantly at Eyreton, and also in the bush at Oxford. The inner antennæ are very small and composed of three joints, the basal one stout, second short and narrowing distally, third about twice as long as the second, much narrower, with a few short setæ at the end (pl. I., fig. 3 a). The outer antennæ consist of seven joints. The basal one is short, the second and third subequal and rather shorter than the fourth; the fifth joint is the longest, and is longer than the flagellum, which consists of two joints, the first short, very slightly longer than broad, the second more than three times as long as the first and followed by a minute terminal joint which bears two or three short setæ; the whole antenna, but more especially the distal portion, is finely hirsute, the hairs being short and delicate, much more so than can be shown in the figure (pl. I., fig. 3 b).

In describing the last segment of the abdomen, Mr. Miers says: “terminal segment much the broadest at the base, with the sides at first converging and then parallel.” In my specimens the sides after converging usually diverge slightly.

The colour varies considerably. It is usually yellowish-brown with darker patches, but some specimens are uniformly black.

Over the whole body the integument is covered with peculiar scale-like markings, each scale being usually more or less pointed at the end (pl. I, fig. 3 c).

Philongria rosea, Koch. (Bate's and Westwood's Brit. Sessile-eyed Crust., vol. ii., p. 460.)

In a previous paper I have identified specimens found at Christchurch and Eyreton as this species, and at the same time adduced reasons for believing that it could not well have been introduced from Europe. Since then I have found specimens precisely similar in the bush at Oxford, so that I think there can be little doubt that it is really a native of New Zealand and has not been introduced.

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I find that my specimens differ from those described by Messrs. Bate and Westwood in one small point, which I had previously overlooked. In theirs the upper surface of the body “is tuberculated, each tubercle emitting a minute seta at its top.” In my specimens the tubercles are not very well marked, and the setæ, though certainly very small, are perhaps rather too large to be called minute, as compared with the animal itself.

I do not, however, consider this difference sufficient to warrant its removal from the European species.

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