40 BULLETIN 63, UNITED STATES NATIONAL MUSEUM. 



GROUP I. CARBONARIA SECTION. 



Legs moderate in length * 1 



Legs long; elytra rather more pointed behind 6 



1. Surface smooth, shining, punctures simple 2 



Surface more strongly sculptured, punctures more or less muricate 5 



2. Smaller species 3 



Larger species 4 



3. Elytra with distinct and rather distant series of moderately sized punctures, 



with a single interstitial series of irregularly spaced, line punctures (form 

 similar to extricata) debili.s. 



4. Elytra with distinct series of rather coarse punctures, punctuation never 



diffuse. 



Pronotum usually widest just before the middle (females at least). East 



of the Colorado River carbonaria. 



Pronotum quite quadrate, sides evenly rounded, equally narrowed before 

 and behind ( form somewhat similar to a smooth, tinely punctate 



gonji). Texas var. soror. 



Elytra usually more or less diffusely punctate, series frequently more or less 

 evident, punctures generally subequal in size. West of the Colorado River. 

 Larger size : 



Apical angles of thorax obtuse, apex feebly emarginate or truncate; 



elytra widest at middle omissa. 



Apical angles subacute, apex moderately emarginate; elytra usually 



widest behind the middle; surface iiolished var. peninsularis. 



Smaller size. Thorax more or less quadrate ; males slender var. pygmiva. 



5. Elytra more or less subasperately sculptured: surface moderately shining, 



punctures irregularly, rather densely placed and submuricate, rarely sub- 



striate Icnaum. 



Elyti'a muricately punctate; surface dull. 



Rather robust. Elytra striato-punctate ; sometimes estriate and dif- 

 fusely i)unctate; intervals more or less moderately convex ohsoleta. 



Moi-e elongate. Elytra sulcate, intervals strongly convex var. porcata. 



G. Surface more or less opaque throughout; pronotum broader ampin. 



Surface more or less shining, pronotum quadrate and polished A'ar. dolosu, 



GROUP I. — QUADRICOLLIS SECTION. 



Anterior spur of the anterior tibife, moderately produced in both sexes 1 



Anterior spur of the anterior tibiie, strongly produced in both sexes (less in 

 the male) 2 



1. Elytra striato-punctate to diffusely punctate. 



Antenme moderate in length; surface more or less shining; epistoma 



coarsely and conliuently punctate quadricoJHK. 



Antemue long. Epistoma more tinely and not confluently punctate. 



Larger species; surface dull var. anthraeina. 



Smaller species; surface i)olished and shining var. lastrans. 



Elytra with punctures irregularly distributed, without serial arrangement, 

 but producing a strongly rugulose appearance by mutual semicoales- 

 cence cuneaticollis. 



2. Elongate species __ : 3 



Shorter, more robust species. : 4 



