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Show 1877.] MR. G. S. BRADY ON BRITISH FRESHWATER MITES. 25 Class ARACHNIDA. Order A C A R I N A. Family TROMBIDIAD,E. Genus RAPHIGNATHUS, Duges. R A P H I G N A T H U S SPINIFRONS, nov. sp. (Plate III. figs. 2-5.) Carapace strong and horny, entire, tapering to an acute point in front, broadly rounded behind, notched at the insertions of the legs. Mandibles (fig. 4) stylet-shaped, projecting about as far as the rostrum ; palps short and thick, obtuse, armed with a few long hairs, and near the apex with four short claw-like setae (fig. 3, b). Coxae contiguous, all arising from the anterior half of the body ; legs five-jointed ; terminal joiut very long and slender, tapering much towards the apex, antepenultimate joint very small, basal joint short. Tbe claws are three in number (fig. 5) on each limb, and are moderately curved. The side of the carapace just behind the rostrum (fig. 3) is produced into four strong spines. The last three joints of all the legs bear numerous long hairs ; and the penultimate joint of the first pair is provided also at its outer apical angle with a single very long seta, which reaches beyond the extremity of the limb itself. Eyes not seen. Colour of the carapace dark brown, opaque ; of the limbs a clear reddish-brown. Length ^ of an inch. Two examples of this species were found amongst a gathering of Entomostraca taken in Crag Lake, Northumberland, in September 1876. It seems to be very nearly allied to a terrestrial species described by Dr. George Johnston, in the ' Transactions of the Berwickshire Naturalists' Club,' under the name of Carabodes nitens. Besides the difference of colour, however, which in Dr. Johnston's species is "pitch-black," there appear to be important distinctions (perhaps of generic value) in the structure of the mandibles and palps ; nor in the description of C. nitens is there any note of spinous armature of the carapace. Genus RHYNCHOLOPHUS, Duges. R H Y N C H O L O P H U S HISPIDUS, nov. sp. (Plate IV. figs. 1-3.) Bodv soft, apparently destitute of any chitinous carapace ; oblong-ovate, "covered with thickly set hairs, which are short on the anterior half but longer behind ; the limbs also are densely hispid, especially towards the distal extremities. Coxae distant ; i. e. the first two pairs of legs are separated from the hinder pairs by a long interval. Mandibles short, included in a short triangular sheath; palps short and stout, the terminal joint wide (fig. 2), and having externally a cushion-like hairy papilla, and internally a short strong claw. The limbs are rather slender, the fourth pair the longest, second shortest, third and first pairs nearly equal: the first two joints are, in all the limbs, small, the rest being nearly of equal length except in the two hinder pairs, where the terminal joints are small. The last joint in all the limbs is considerably dilated (fig. 3), and is armed with two |