OCR Text |
Show 1873.] REV. O. P. CAMBRIDGE ON SIBERIAN SPIDERS. 441 or less (though for the most part slightly) suffused with a dusky greenish sooty hue. In form and structure the cephalothorax is of the ordinary type ; the clypeus is equal to half that of the facial space ; and the cephalothorax has several long bristly hairs in a longitudinal series along the central line of the upperside. The eyes are of moderate size, closely grouped together, and seated on almost confluent black spots ; those of the hind central pair are further from each other than each is from the hind lateral on its side, the interval being near about an eye's diameter ; those of each lateral pair are contiguous to each other, and placed obliquely on a slight tubercle ; those of the fore central pair are the smallest of the eight, contiguous to each other, and each is separated by no more than half an eye's diameter from the fore lateral on its side. The interval between each of the fore centrals and the hind central nearest to it is rather less than the diameter of the latter. The legs are short and slender; their relative length 1, 4, 2, 3, the difference between 1 and 4 being very slight, if any. They are furnished sparingly with hairs and a few slender, mostly erect, spine-like bristles. The palpi are short. The radial and cubital joints about equal in length, but very short; the former a little produced in front at its fore extremity, but with no marked prominence or apophysis. The digital joint is small, oval ; and the palpal organs are well developed and complex, with various corneous processes, and a small and short but conspicuous, prominent, pointed, curved, black spine near their extremity on the outer side. The abdomen is oval, moderately convex above; when in spirit of wine (but probably not before immersion) there are visible various pale lines and spots, forming a regular pattern on its upper part and sides, similar in this to many other species of Erigone. The female resembles the male in general structure and colours. The epigyne connected with the sexual aperture is (like that of many other Spiders) prominent and of a peculiar and distinctive form ; in the prominence of this part this species shows a near approach to the genus Linyphia. It is closely allied to L. decens (Cambr.), but may easily be distinguished by the larger size and closer grouping of the eyes, as well as by its clearer and brighter colours and the armature of the legs. From L. oblita (Cambr.), again, it may be distinguished by similar differences in the same characters. Both sexes in the adult state were received from M . Taczanowski in the Siberian collection. ERIGONE (NERIENE) PROLATA, sp. n. (Plate XL. fig. 7.) Adult male, length 1 line. In general structure and form this Spider is of the ordinary type, and much resembles in those respects many allied species on the borders of the genus Linyphia. The whole of the fore part is of a yellowish-brown colour, that of the cephalothorax and sternum being rather darker than that of the legs. The normal grooves and indenta- |