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Show 1877.] REV. O. P. CAMBRIDGE ON NEW ARANEIDEA. 573 Fam. DINOPIDES. Until lately one genus alone of this group (Dinopis, Macleay) had been characterized. It has always appeared to me impossible to place Dinopis in any known or recognized family group ; and consequently I have long since constituted it a family of itself, placing it between the Lycosides and Salticides, rather for want of a hetter place for it than for any really close affinity to either of them. It is more probable that its place will some day be found to be much nearer to the Agelenides than to either the Lycosides or Salticides. Dr. Ludwig Koch, writing in 1867 (Verh. k.-k. zool.-bot. Gesell. in Wien, 1867, p. 230), says that the position of Dinopis is without any doubt in the family Eresides, giving as a proof the position of the eyes and possession of calamistra and inframamillary organ. It would seem, however, scarcely possible to place in juxtaposition two Spiders more unlike each other than Dinopis and Eresus, whether we consider the general form, or any special point of structure from which a family affinity could be deduced. The mere position of the eyes is quite insufficient. Podophthalma has an eye-position very closely resembling Dinopis; and between other widely separated genera there may also be often found a similar eye-position. Relying upon this only, Walckenaer once placed a Theraphosid (ldiops) in the genus Sphasus; and as regards calamistra and the mamillary organ, these may certainly be considered of family value in some groups of genera possessing them, as in Dictyna, Amaurobius, Titanoeca, and Lethia ; but when we find them in such widely different Spiders as Filistata, QHcobius, and Rhion, all family value, at least with respect to them, vanishes. So, it appears to me, it is also in regard to Dinopis, where the flattened cephalothorax, enormous central pair of eyes, long and excessively slender legs, with a very peculiar form of maxillae, labium, and sternum, must have far more weight than the calamistra and general position of the eyes taken by themselves. M. Simon has recently (Bull. Soc. Zool. de France, 1876, p. 218) characterized a second genus (Menneus) unmistakably allied to Dinopis, but, along with some minor characters, differing remarkably in having the tarsi of the first pair of legs subdivided. Menneus has also calamistra; and so also has another Spider, allied both to Dinopis and Menneus, and upon which I propose presently to found a third genus of the family Dinopides. This Spider, for which I propose the generic name Avella, has the flattened cephalothorax, the long slender legs, the peculiar maxillae and labium, as well as the general eye-position of Dinopis; but the central pair of eyes are but little larger than the rest. With Menneus it agrees in having the tarsi of the first pair of legs subdivided, though it seems to me, with respect to other generic characters, quite distinct. It however possesses calamistra and an inframamillary organ (though the calamistra were of rather a peculiar nature). It is therefore probable that these portions of structure will here also prove a good family character within the limits of the Dinopid group; but this remains to be proved. Of course the family character thus attached |