THYCE AND POLYPHYLLA 345 



dense at the segmental apices as usual. Length 25.0-27.0 mm.; 



width 12.013.0 mm. Six specimens. 



Female nearly like the male but more ventricose, the prothorax 



relatively smaller, the clypeus very much shorter and with more 



rounded angles but deeply concave; antennal club small, only about 



half as long as the stem; pygidium not quite so densely squamose. 



Length 26.0 mm.; width 12.8 mm. One example. 



New Mexico (Jemez Springs and Las Vegas) and Colorado 



(Salida). Kansas (Platte River), Say decemlineata Say 



A Form narrower than in the preceding and rather smaller in size, 

 black, almost similarly clothed, except that the scales are much 

 more numerous throughout on the vertex and the erect hairs there 

 more abundant and longer; prothorax nearly similar throughout; 

 scutellum squamose almost throughout, less densely toward the 

 sides, glabrous at apex; elytra narrower but otherwise similar, 

 the narrow dense white lines bordered at each side by still more 

 conspicuous smooth glabrous lateral margins of the intervals; 

 pygidium with a very dense covering of small pointed white scales, 

 mixed sparingly with minute hairs, the median line narrowly 

 glabrous, except at base and apex; abdomen intense black through- 

 out; legs unusually slender, ferruginous, the femora piceous; 

 middle tarsi evidently shorter than the tibiae. Female not known. 

 Length 23.0 mm.; width 10.5 mm. Wyoming. One specimen. 



parilis n. subsp. 



B Form almost exactly as in parilis but with more yellowish dense 

 vittse, black throughout, the legs red-brown, the antennae dark 

 brown; head as in parilis, the antennal club a little shorter and 

 thicker, not quite three times as long as the stem; prothorax 

 similar in general outline but still shorter, much more than twice 

 as wide as long, the vestiture sparse and composed of very broad 

 scales, about two and one-half times as long as wide, sharply 

 pointed, the dense vittae similar, the punctures much smaller; 

 scutellum densely squamose, except at the sides; elytra throughout 

 nearly as in parilis; pygidium very different, larger, much wider 

 than long, similarly very densely squamulose throughout, more 

 sparsely and with some intermixed whitish hairs apically, but 

 without trace of the narrow glabrous line of parilis; abdomen black 

 throughout; middle tarsi slightly shorter than the tibiae. Female 

 unknown. Length 23.0 mm.; width 10.5 mm. Nevada. 



laticauda n. subsp. 



C Form more oval than in lo-lineata and decidedly smaller in size, 

 dark castaneous, the prothorax dark rufous, the abdomen black, 

 pallescent at tip; sparser vestiture pale yellow, the dense vittae 

 pure white; head moderate, the vertex with numerous rather long 

 erect hairs and scattered scales, the latter dense toward the eyes; 

 clypeus truncate, with parallel sides and blunt angles, shallowly 

 concave, rather evenly and closely clothed with finely attenuate 

 scales, gradually dense apically; antennal club barely over two 

 and one-half times as long as the stem, pale brownish-yellow; 

 prothorax nearly as in lo-lineata but less sparsely punctate; 



