THYCE AND POLYPHYLLA 309 



long, the sides subparallel and nearly straight to the middle, there 

 narrowly rounded and thence converging and nearly straight to the 

 apex, finely and only very feebly serrulate; apex feebly sinuate, 

 two-thirds as wide as the base, which is gradually very strongly 

 lobed as usual, the hind angles obtuse but not evidently rounded, 

 slightly blunt; surface finely, very closely punctate and densely 

 clothed with rather long subdecumbent, basally slightly broadened 

 hairs, with others long, sparser, finer and erect bristling throughout,, 

 the vestiture a little denser along the middle and broadly near the 

 sides as usual; scutellum very densely, decumbently pubescent 

 throughout; elytra two-fifths longer than wide and fully a third wider 

 than the prothorax, finely, densely, subrugulosely punctate and with 

 decumbent and rather long slender close-set stiff but scarcely at all 

 squamiform hairs; lateral impression extending behind the middle; 

 pygidium wider than long, narrowly rounded at apex, covered 

 densely with small narrow squamules; hind tibial fringe long, the 

 hind tarsi shorter than the tibiae, first tooth of the anterior tibiae very 

 short and broadly obtuse. Length (cf) 20.5 mm.; width 9.7 mm. 

 Mojave Desert carpenter! Lee. 



Body rather shorter and less convex than in carpenteri, moderately shining, 

 pale red-brown throughout, the vestiture yellowish; head rather 

 strongly, densely punctate, and with long erect dense hairs through- 

 out; clypeus with finer and well separated punctures, bearing short 

 and stiff but rather sparse hairs, the angles obtuse but distinct, the 

 parallel sides and the apex distinctly and subequally arcuate; last 

 palpal joint narrower than in the preceding but not one-half as long 

 as the antennal club, having a very deep excavation extending from 

 near the bas<e to apical fifth or sixth; prothorax nearly similar in form 

 to the preceding but with the sides diverging and straight from base 

 to behind the middle and converging and feebly arcuate from the 

 submedian rounded angle to the apex, feebly serrulate, the basal 

 angles obtuse but very distinct, not rounded ; surface not very coarsely 

 but deeply, closely puncta.te and with very long, fine, erect bristling 

 hairs throughout; at the surface shorter stiffer and more decumbent 

 but scarcely squamiform hairs are moderately closely distributed; 

 scutellum with rather long shaggy hair throughout; elytra only a 

 fourth longer than wide, nearly a third wider than the prothorax, 

 more abruptly and transversely obtuse at apex than in carpenteri, 

 the oblique lateral impression not extending behind the middle, 

 feebly rugulose, the punctures fine and sparse, each with a moder- 

 ately short and rather coarse hair, the hairs well separated, not quite 

 decumbent, a little longer but only slightly more close-set along the 

 suture; pygidium wider than long, narrowly parabolic at tip, not 

 densely clothed with short stiff hairs; abdomen with similar but 

 closer hairs; first tooth of the anterior tibiae short and broadly obtuse. 

 Length (cf) 17.5-20.0 mm.; width 9.0-10.0 mm. California (Los 

 Angeles), J. J. Rivers riversi Csy. 



Body in the female much larger than the male of riversi and with closer 

 vestiture, pale and feebly shining reddish-brown in color throughout; 

 head densely clothed with long, suberect yellowish hairs, the tumor 



