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Show 1875.] MR. G. S. BRADY ON BRITISH MARINE MITES. 309 tus, Latreille, as figured by Dr. Johnson in his monograph of the Acarides of Berwickshire*, that I cannot doubt the propriety of referring it to the same genus. Genus HALARACHNE, Allman. Halarachne halichceri, Allman, Ann. & Mag. Nat. Hist. vol. xx. 1847, p. 47. Parasitic in the posterior nares of a Seal (Halichcerus gryphus). Fam. ORIBATIDCE. Genus H A L A C A R U S , Gosse. H A L A C A R U S R H O D O S T I G M A , Gosse, Ann. & Mag. Nat. Hist. ser. 2, vol. xvi. (1855), pl. 3. figs. 1-5. Halacarus granulatus, Hodge, Trans. Tyneside Nat. F. C. vol. v. p. 299, pl. 16. figs. 4, 5. Halacarus oculatus, Hodge, Trans. Tyneside Nat. F. C. vol. v. p. 300, pl. 16. figs. 8, 9. " Body divided above and below; claw of palpus slender, little curved ; legs nearly equal; thighs of first pair ventricose ; claws all simple ; whole surface minutely punctured. " Length T V of an inch from anus to tip of rostrum: colour pellucid whitish, stained with pale red on the anterior half; above and below studded with punctures, which under a high power take the form of rosettes or the spots on a panther's coat; the punctures are conspicuous on the first thighs, but are scarcely visible on the other limbs; the haunches are moderately distant at their origin, springing from the margin of the body, the shield being notched to give them exit; the third joint of the legs is the largest, much swollen in the first pair ; the fifth is also large; and the sixth is long but slender, tapering abruptly from the middle; the claws are simple hooks, much curved, neither pectinated nor tipped with an accessory piece, but the joint from which they spring is tipped with two nearly parallel styles : the legs are equal in length. " The shield of the body above is subtruncate in front, but projects in a small median point, long-oval, with a transverse sulcus at the origin of the second legs. Below, the body has two transverse divisions-one at the origin of the first legs, another at the origin of the third. " The rostrum forms a thick bulb, tapering to a point, from which, during life, I observed two apparently soft, flexible, filiform, divergent organs (mandibles ?) protruded and retracted. Palpus of four joints, of which the second is by far the largest; terminal joint slightly curved, pointed, and furnished near the base with two strong bristles on the inner side and one on the outer. All the joints of the legs are armed with a few short bristles. The vulva occupies a large oval area at the hind part of the venter; and the anus is terminal." * Transactions of the Berwickshire Naturalists' Field-Club, vols. ii. & iii. |