OCR Text |
Show 574 REV. O. P. CAMBRIDGE ON NEW ARANEIDEA. [June 19, to these curious points of structure would at once fail if an undoubted Dinopid were found without them. Gen. nov. AVELLA. Cephalothorax longer than broad, oval behind, constricted laterally at the caput, and truncated in front; the lower corners of the clypeus prolonged into eye-bearing tubercular prominences; upper surface much flattened, the thorax and caput being on the same low level. The caput runs in a straight line to the middle pair of eyes, when it drops abruptly, at right angles, to the falces. Eyes small, in three transverse rows, 4, 2, 2, and not differing greatly in size ; the foremost row (of four) is strongly curved, the convexity of the curve directed backwards; the laterals of this row are placed at the extremity of cylindrical tubercles springing from the corners of the clypeus. Those of the second row are a little the largest of the eight. Those of the third or posterior row form a line not nearly so long as that formed by those of the first row. Legs long, slender; relative length 1, 2, 4, 3 - 1 and 2 greatly exceeding 3 and 4 in length ; the tarsi of the first pair subdivided. Each tarsus ends with three curved claws, of which the superior pair are pectinated ; and there is a calamistrum on the metatarsus of each of the fourth pair. Palpi short, slender, and terminating with a single curved pectinated claw. Falces long, strong, and divergent. Maxillee long, strong, considerably constricted just above the insertion of the palpi, and thence greatly divergent, or bent outwards, and rounded at their extremities. Labium oblong but broader at the base than at the apex, which is truncated ; its length slightly exceeds one half that of the maxillae. Sternum of a somewhat subtriangular form, but much elongated. Abdomen long, broadest in the middle, where there is a strong prominence on each side, with a supernumerary mamillary organ in front of the ordinary spinners. AVELLA DESPICIENS, sp. n. (Plate LVII. fig. 10.) Adult female, length rather over 4\ lines. The cephalothorax is of a yellow-brown colour, with a broad central longitudinal band of a paler hue ; this band runs through to the central pair of eyes; it is rather wider on the caput than on the thorax, and is thickly clothed with a grey pubescence, the rest of the cephalothorax being thinly clothed with similar pubescence. The area comprised by the six foremost eyes is of a rather chocolate red-brown colour. The eyes may be described not only as in three transverse rows, but as also in two quadrangular figures, a large one with a small one in the middle of it; the foremost pair of the central quadrangle are the smallest of the eight, and separated from each other by about three diameters, and from the hinder pair by about two; the hinder pair are considerably larger and form a longer line than the |