1116 



FAMILY Lin. — CHRYS'OMELIDiE. 



XII. Exema Lac, 1849. 



Two very small species represent this genus in the eastern 

 United States, both of which occur in Indiana. 



KEY TO THE SPECIES OF EXEMA. 



a. Dark cupreous, bronzed; thorax strigose. 205G. dispae. 



aa. Black without metallic lustre; thorax punctate. 2057. gibbeb, 



2056 (6605a). Exema dispae Lac. Mon., II, 1848, 850. 



Oblong, subquadrate. Blackish, feebly bronzed; antenna? and labrum 

 usually dull yellow. Thorax finely strigose, the crest of the median tuber- 

 cle sulcate but not bifid. Elytra with tubercles as in C. plicata; intervals 

 with coarse, deep, rather close-set punctures. Presternum concave. Length 

 2.5-3 mm. 



Throughout the State ; frequent. June 9-September 25. Taken 

 by sweeping herbage along roadsides. 



2057 (6604). Exema gibbee Fabr., Suppl. Ent. Syst, 1798, 112. 

 Oblong-quadrate. Black, without lustre, often more or less spotted 



with yellow ; labrum and legs yellow. Thorax densely punctate, the crest 

 with a shallow median groove. Elytra with oblique oblong tubercles ; in- 

 tervals coarsely and rather closely punctate. Prosternum flat. Length 

 2-2.5 mm. 



Starke, Marshall, Putnam and Posey counties; rare. May 11- 

 June 18. Taken by sweeping. 



Tribe VI. CRYPTOCEPHALINI. 



To this tribe belong numerous small, robust, more or less cylin- 

 drical species having the antenna? slender, filiform, longer than head 

 and thorax, rarely (Monacluis) shorter and subserrate; thorax mar- 

 gined, as wide as elytra and closely applied to the latter ; eyes large, 

 more or less emarginate ; elytra not tuberculate, marked with rows 

 of punctures, rather short, leaving the tip of abdomen exposed; 

 prosternum wide, separating the front coxa?, which are rounded, not 

 prominent, their cavities enclosed behind; middle and hind coxa? 

 each widely separated; tarsi dilated, claws usually simple, rarely 

 broadly dilated at base. The tribe is founded upon the genus 

 Crypt oeephalus, of Geoffroy, a term meaning "concealed head," 

 and given to these insects because the head is so deeply immersed in 

 the strongly convex thorax that it can be scarcely or not at all seen 

 when viewed from above. In color they are usually variegated with 

 various combinations of spots or stripes which are sometimes very 

 inconstant, so that numerous varieties have been named. 



Seven genera compose the tribe, all of which are represented in 

 the State. In addition to the papers cited under the family head- 

 ing, the following treat especially of these genera : 



