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Show 1873.] SPIDERS F R O M ST. H E L E N A . 215 cephalothorax ; and the fangs, which are also equal to the falces in length, are strong, sharp-pointed, of a deep-black chestnut-brown colour, tolerably straight in the middle, but bent at both ends; a constriction towards their extremity gives them at first sight the appearance of being articulated at that point. The maxillae are of the normal form, and are thickly furnished with strong black hairs on their inner margins (next to the falces). The labium is broadish oblong in form, strongly emarginate at the apex, and does not much exceed in length half that of the maxillae ; its colour is a dark chestnut-brown. The abdomen is short-oval, and projects over the base of the cephalothorax; it is of a dull yellow colour, very sparingly clothed with short fine hairs, and marked on its upperside, near the middle, with four impressed dots of a rusty hue, forming a square, whose fore side is the shortest. A single example of this exceedingly fine and distinct Cheiracanthium was contained in Mr. Melliss's St.-Helena collection; and I have great pleasure in connecting with it the name of that gentleman. By the size of the falces it is allied to C. italicum (Canestrini and Pavesi, Atti della Soc. Ital. di Scienze Nat. xi. fasc. 3, 1848, p. 114, separate copy?; also Arch. p. Zool. Genova, ser. 2, vol. iii. tab. 4. fig. 3) ; but it m ay be distinguished at a glance by the remarkable difference in the character and relative proportion of the palpal joints, as well as by the greater length of the legs of the first pair of the present species, and the less size of the Spider itself. CHEIRACANTHIUM PLANUM, sp. n. (Plate XXIV. fig. 5.) Adult male, length 4 lines. The cephalothorax of this species is of a rather broad oval, only slightly constricted laterally in front, and flattened above, its upper convexity being very slight, and at the fore part it is somewhat squarely truncated ; it is of a yellow colour, slightly suffused in front with pale reddish brown ; the space enclosed by the four central eyes is dusky blackish ; and from them an indistinct suffused line of the same runs back along the middle, disappearing on the hinder slope. The eyes are in two rows, and occupy a broad transverse, but very narrow longitudinal area, the fore lateral eyes (when looked at from the front) being very nearly as wide apart as the width of the two falces ; the clypeus is obsolete, owing to the fore central eyes being placed immediately upon the fore marginal line of the caput. The eyes are small, and do not differ much in size; those of tbe fore central pair are rather more than an eye's diameter distant from each other, and each is considerably further removed from the fore lateral eye on its side ; those of the hind central pair are further from each other than those of the fore central pair, the four central eyes forming a square whose fore side is the shortest; and the space which separates the central eyes is less than that which separates each from the hind lateral on its side, in about the same proportion as above mentioned in regard to the eyes of the foremost row; those |