THE CANADIAN ENTOMOLOGIST. 31 



b. Elytra entirely blue, green, violaceous, blackish or testaceous. 

 c. Body never entirely black beneath. 



Elytra bright blue or green, thorax smooth ; body beneath 



entirely pale. .18-. 28 in gibbitarsa, Say. 



Elytra violaceous or greenish-black, thorax more or less 

 distinctly punctate, body beneath in great part dark, 

 thorax yellowish with a large piceous space or M-like 



mark blackish. .16-. 28 in vians, 111. 



cc. Body entirely black beneath, upper surface dull black, im- 



punctate. .18-. 22 in lugens, Lee. 



bb. Elytra with pale margin, disk violaceous or bluish. 



Thorax and elytra coarsely and closely punctate. 



.20-.26 in thoracica, Fabr. 



Thorax and elytra indistinctly punctured ; elytra brilliant 



violaceous. .20-24 i" flavocyanea, Cr. 



AA. Antennae slender, equal to or greater than one-half the length of tlie 

 body ; front of head vertical ; elytra with explanate margin. 



d. Elytra broadly oval, sides much arcuate, coarsely punc- 

 tate ; may be yellowish with indistinct vittse, or black 

 with only the margin pale. .14-. 20 in. .limbalis. Mels. 

 dd. Elytra with sides feebly arcuate or nearly parallel ; yel- 

 lowish, with indistinct brown spots and bands or with 

 the disk entirely piceous. 

 e. Thorax very coarsely punctured ; elytra 

 with a more or less evident costa ex- 

 tending from humeri to apex, yellow- 

 ish with blackish spots which some- 

 times coalesce to form an X, behind 

 which is an irregular transverse band. 

 .14-. 16 in. (fig. c^)... .sexmaculata, 111. 

 ee. Thorax finely punctured or smooth. 



Head coarsely punctate, punctures •*""'• 5. 



closely placed ; yellowish ; elytra with base, suture, 

 and often two spots on each, brown. .14-. 16 



'1 Slitter alls, Fabr. 



Head sparsely punctate or nearly smooth ; thorax 



often entirely yellow, or may be piceous with the 



• margin pale ; elytra piceous with yellow margin, 



