ZOOL— Vol. I.] BANKS— MEXICAN ARACHNIDA. 235 



Cephalothorax dark brown, covered with a rather long, reddish brown pu- 

 bescence, and especially at the sides, behind pars cephalica with white hairs, 

 in the posterior part at base with a triangular yellow spot. Mandibles and 

 maxilla? brownish yellow, the latter at the inner sides pale; labium at base 

 yellowish, whitish at tip; sternum yellowish brown with a black border. Legs 

 1 st pair, femur and patella dark brown, the other joints light yellow, with the 

 distal end dark infuscated, apical half of metatarsus deep black, sometimes a 

 pale spot on femur beyond the middle; 2nd pair, femur dark brown, with a 

 yellow ring near tip; patella dark brown; tibia and metatarsus light yellow, 

 with a broad brown band at the end, and a narrow brown ring near the mid- 

 dle; tarsus light yellow, the distal end dark brown; 3rd and 4th pairs of legs, 

 the femur yellowish, with the distal end dark infuscated and a dark ring close 

 behind; tibia and metatarsus as femur, and tarsus light yellow, with the tip 

 darkened. Abdomen grayish, with four white dots, a short basal longitudinal 

 middle line and the sides darkened. 



Cephalothorax nearly as broad as long, flattened; both eye-rows recurved, 

 the four M. E. form a trapeze which is higher than broad posteriorly; man- 

 dibles long, robust, parallel, and vertical, claw weak; maxillae broad at tips, 

 narrow at base, truncate in front; labium narrower at base than in middle, 

 pointed at tip; sternum long and narrow, covered with white scaly hairs; abdo- 

 men triangular; i. e., elevated at the first third by two hunches, drawn out at 

 blunt tuberances, which give the dorsal surface a geniculated appearance. 



Three specimens from Guaymas. 



90. Uloborus albineus Marx ms. 



Plate XV, Fig. 18. 

 Female, long 4.2 mm. 



Cephax. long 1.5, broad in middle 1.3; broad in front .6. 

 Abdomen 3.5, thick at the hunches 3. 

 Femur I 2, pat. and tibia 2. metat. 2. tarsus 1. 

 II 1.4 1.4 1. .5. 



III 1. 1. .6 .5. 



IV r.6 2. 1.2 1. 



Cephalothorax pale brownish yellow, pars cephalica covered with reddish 

 brown hairs, which run over the whole dorsal surface, with the exception of 

 a white margin at the sides; two black lines obliquely running from the base 

 over the post-thorax, inclosing a pale yellowish triangular spot; mandibles 

 and maxillae brownish yellow, the latter with the inner margin white; labium 

 at base yellow, at tip white; sternum brownish yellow, with black, long, stiff 

 hairs. Legs pale yellowish, with pale brownish rings; only the distal half ol 

 metatarsus I is deep black. Abdomen white, with a long irregular blackish 

 spot on the middle line behind the two hunches, hardly reaching to the apex. 



Cephalothorax nearly as broad as long; both eye-rows recurved, the an- 

 terior M. E. by their diameter separated from each other, and larger than the 

 S. E. ; the four M. E. form a trapeze, broader than long, narrower in front; the 

 anterior S. E. more separated from the anterior M. E. than they are them- 

 selves; mandibles, in front highly arched, parallel, vertical; maxillae narrow 



