236 MEMOIRS ON THE COLEOPTERA 



Prothorax and other general characters as in tumidus but larger, not quite 

 so black, the abdomen pale testaceous with a narrow apical border 

 on all the segments deep black; surface very highly polished; head 

 larger, rather strongly swollen basally beyond the eyes, which are 

 separated by very much more than their own width; antenna? (9 ) 

 with the last joint much longer, fully as long as the preceding and 

 three times as long as wide; prothorax nearly similar, except that 

 the very large and prominent, finely acute and scarcely at all reflexed 

 median teeth are horizontal in plane, their anterior slope very ob- 

 tusely unidentate; scutellum nearly similar but more deeply canal- 

 iculate; elytra nearly similar but much more dehiscent behind the 

 middle, still more finely and very sparsely punctate, with the three 

 raised lines very fine and feeble though evident; inferior groove of 

 the hind tarsi becoming very broad on the basal joint, distinct 

 through the first three joints of the intermediate; anterior and 

 middle femora scarcely at all compressed; punctulation toward the 

 sides of the metasternum much finer and denser. Length ( 9 ) 56.0 

 mm.; width 22.0 mm.; width of head 10.4 mm.; length of prothorax 

 9.0 mm. Arizona (locality not specified) vastus n. sp. 



Prothorax very much shorter and less convex, being as usual throughout 

 the genus in these respects 8 



8 Color black, the upper surface shining throughout. Body intense 

 black above and beneath (cf ), or picescent beneath (9 ), moderately 

 stout; head about as wide at base as across the eyes, the latter 

 separated by a little less (cf) to sensibly more (9) than their own 

 width; antennae as usual in form, deep black, with the last joint 

 not quite as long as the preceding, nearly four times as long as wide, 

 with the inner face beveled apically (cf ), or piceous-black, with the 

 last joint shorter than the preceding, a little more than twice as 

 long as wide, less compressed, more oval and not beveled apically 

 ( 9 ) ; prothorax very much more than twice as wide as long, with 

 rather small but deep, sparse and irregularly distributed punctures, 

 the anterior slope of the middle teeth not modified, straight; scutel- 

 lum very broadly rounded at apex; elytra a fourth to a fifth wider 

 than the prothorax, with the humeral angles only feebly tumid, the 

 sides rather rapidly converging and broadly arcuate thence to the 

 somewhat narrowly rounded apices, three-fourths longer than wide, 

 the raised lines very feeble, obsolescent in the female, the punctures 

 rather strong, moderately close, everywhere widely separated, the 

 surface sometimes becoming feebly rugose medially toward base ( 9 ) ; 

 metasternum pubescent throughout (cf), or very minutely, not 

 densely punctulate and finely pubescent toward the sides only (9 ); 

 middle and hind tarsi canaliculate throughout in both sexes, the 

 channel not much wider on the first joint; male very much smaller 

 than the female. Length (cf ) 29.0, (9 ) 46.0-47.0 mm.; width (cf ) 

 1 1. 8, (9 ) 18.0-18.2 mm.; length of prothorax (9 ) 6.25 mm.; width of 

 head (9) 8.3-8.8 mm. New Mexico (Jemez Springs), Woodgate. 



tristis n. sp. 



Color very dark castaneous, the elytra strongly alutaceous in lustre. 

 Body narrower in form, with relatively much larger head, the under 



