NEW WESTERN SPIDERS By Ralph V. Chamberlin. Most of the new forms of spiders described below were found in collections made by the writer in Utah in the latter part of August and the early part of September, 1917. The collections were made on Chalk Creek in the Uintah Mts., at elevations of from 7,300 to 10,000 ft. and at and near Fill-more, Millard Co. In addition to the spiders from Utah, a number of new forms from other localities noted while identi-fying the collections mentioned are here described. DICTYNID^. Amaurobius utahensis sp. nov. Male — Caraijacc, sternum, labium, endites and legs yellow, without any reddish tinge, the legs unmarked. Abdomen blackish, the anterior middle region of dorsum obscure yellow, the posterior half with dark marks which are, excepting the first ones, only vaguely separated from each other. Anterior row of eyes procurved; medians close together, but more than their diameter from the laterals. Posterior eyes much smaller than the anterior ones, the medians slightly smaller than the laterals, about twice their diameter apart and about twice as far from the laterals. Area of median eyes rectangular, being as wide behind as in front, longer than wide. Distal joints of palpus heavier than in nevadensis. Tibial apophyses very similar to those of the species mentioned; but the exterior one distally less uncate, the median one basally broader and more narrowed distad, and the mesal one obviously broader and shorter and differing particularly in being united with or carried forward on a common base with the median one m^uch farther, the ridge uniting the two in nevadensis being slight or obsolete. Length. 11.5 mm. Length of cephalothorax, 6.1 mm. Length of tib. + pat. I, ().4 mm.; of tib. + pat. IV, ().7 mm. Type— M. C. Z. 414, Utah: Fillmore. This species is nearest A. nevadensis Simon. It is a more robust species, wholly lacking the reddish cast characteristic of nevadensis. It differs chiefly otherwise in the details of the male palpus as indicated above and also presents minor differences in the eyes. 239
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