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Show 686 REV. O. P. CAMBRIDGE ON NEW [Nov. 18, in 1879 from Captain Hutton. In general appearance and colours it reminds one strongly of Spiders of the family Palpimanides, from which, however, it is clearly distinct, and its true position is, as it appears to me, among the Enyoides, near the genus Ceto, Sim., to which it seems to be tolerably nearly allied, though differing in the relative length and breadth of the cephalothorax, as well as in the form of tbe maxillee and labium, and in other structural points. Fam. AGELENIDES. ROBSONIA, gen. nov. Cephalothorax short, broad, truncated before, not very convex above ; the fore extremity of the caput scarcely narrower than the thorax; lateral marginal constrictions at the caput very slight. Eyes small, subequal, in two transverse subparallel rows, the anterior of which is the shortest and very close to the fore margin of the caput, rendering the clypeus almost obsolete. The posterior row of eyes is slightly curved, the convexity of the curve directed forwards; the four central eyes are the smallest. Legs moderate in length, slender, 1, 4, 2, 3, furnished with very fine prominent hairs, some of which, on the undersides, are very long. On the tarsi and metatarsi of the third and fourth pairs are a very few short spines. Tarsal claws three in number ; the superior pair strong, slightly curved, and furnished with about ten fine denti-culations or pectinations ; the inferior claw very abruptly bent downwards close to its base. The hairs are strongest and most numerous beneath the fore extremities of the metatarsi and tarsi of the second, third, and fourth pairs, but do not constitute either a scopula or claw-tuft properly so-called. Falces very long, strong, straight, prominent, and almost cylindrical ; the fang, when at rest, directed backwards, slightly obliquely, but approaching nearly to the position characteristic of the Thera-phosides. Each falx is furnished with a row of teeth almost throughout its whole length on the inner side of the fang as it lies at rest, and two others form a short row on the opposite side of the base of the fang. Maxillee long, straight, greatly enlarged at the hinder part where the palpi are inserted, and constricted immediately above that point; their outline is rounded to the extremity, where they are obliquely truncated in a slightly hollow line inwards. Labium long, about two thirds the length of the maxillee, of a broadish oblong-oval form, truncated both at the base and apex. Sternum heart-shaped. Abdomen oviform : spinners six, rather short, but all of equal length, the two middle ones being of unusual size, almost equal, in fact, to tbe rest. The affinities of this genus are rather puzzling. Were it not for the three terminal tarsal claws, it would seem to come easily into the family Drassides. The form of the maxillae and labium point to a relationship with the Dysderides. It must, however, I think, be |