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Show 1 9 0 5 .] BRITISH MITES OF THE FAMILY (JHIBATIIJ/E. Fam. O r i b a t i d a Subfam. O ribatljwE. Gen. O r ib a t a Latreille. O r ib a t a fu r o a t a , sp. nov. (Plate XIX. fig. 1.) Adult. Length 500 ft. Colour dark brown, nearly black. Surface polished. Lamellte, blades on edge with very long cylindrical cusps, the whole extremity of the cusp being occupied by the base of the long lamellar hair. Translamella an inverted "V. Interlamellar hairs present. Pseudostigmatic organs long, sub-clavate, directed forwards and upwards. Pteromorphse small. Claws monodactyle. Genital and anal orifices moderately far apart, shaped like the keystone of an arch ; the anal considerably the larger. Nymph and larva unknown. Two specimens found in moss from Austwick Bog, Yorkshire, in May 1904. There is no danger of confusing this very distinct species with either of the other two known British monodactyle Oribatas, 0. fiosigera and 0 . parmettice. The first is very minute, while the second has hairs on the notogaster, and short clavate pseudostigmatic organs. O r ib at a omis sa, sp. n o v . (Plate XIX. fig. 2.) Adult. Length 700 /i. Colour dark brown. Surface highly polished and shining. Body distinctly broadest in the middle. Lamellae, blades on edge, with a long sharp-pointed cusp standing free, the lamellar hairs springing from the inner angle of the cusps. No translamella. Claws tridactyle. Not rare in moss, at Cambridge. Nymph and larva unknown. We think it likely that this species has hitherto been overlooked on account of its resemblance to the common and extremely variable species 0. lapidctria, and in spite of the different facies, due chiefly to its barrel-shaped body and polished surface (destitute of a light spot), there seemed to be few clear distinctive characters. The~absence of any trace of a translamella, and the sharp-pointed c.usps, are, however, good characteristics. Though occurring in the same neighbourhood their habitat is different, 0. omissa being exclusively found in moss, nor have we met with any intermediate forms. O r ib a t a r u b en s C. L. Koch. This very distinct species occurred in Sphagnum from heath-pools at B o u r n em o u th in October 1905. It is about 500 ,, in length, chestnut-coloured, and with very long legs. It is now for the first time recorded as British. |