FLEA-BEETLES. 



The hind tibiae are not grooved on the 

 outer edge, but slightly excavated near the 

 tip and with a spur at the middle beneath. P. vittata 

 (Plate LXXXIII) is common all summer on cabbage and 

 other Cruciferae. The fifth joint of the antennas is longer 

 than either the fourth or the sixth; the male has the fifth 

 antennal joint thickened. 



The two common, garden species are 

 distinguished from the others by having 

 no longitudinal fold along the sides of the elytra; by the 

 antennae and legs being black; and by a deep groove 

 which extends completely across the pronotum in front 

 of the base. H. chalybea is the Grape Flea-beetle. It is 

 usually not less than .17 in. long; metallic blue, rarely 

 greenish; pronotum distinctly narrowed in front. H. 

 ignita is usually not more than .17 in. long; color varies 

 from a coppery-golden lustre, through greenish, to dark 

 blue; pronotum only slightly narrowed in front. In addi- 

 tion to feeding on a variety of wild plants it attacks straw- 

 berries and roses. 



The following have the front coxal cavities closed 

 behind; the last joint of the hind tarsi is not inflated, 

 usually slender, although sometimes thickened in a side 

 view. The antennas of Blepharida are 12- jointed, instead 

 of 1 1 ; tarsal claws bifid. ChcEtocnema has the hind tibiae 

 sinuate near the apex and with a distinct tooth on the outer 

 margin. Epitrix (elytra with rows of stiff hairs) and Crepi- 

 dodera (elytra without hairs; antennas shorter than the 

 body) have a distinct transverse impression in front of the 

 base of the pronotum. The following lack such an im- 

 pression: Dibolia (hind tibial spur broad, emarginate, or 

 bifid at apex), Mantura (pronotum with a short, deep 

 longitudinal impression on each side near the base), and 

 Systena (pronotum without any impression). 



C. confinis is the species likely to be 



Chaetocnema J . , 



noticed first. It reeds on sweet-potato, 

 morning-glory, and other Convolvulaceas. It is less than 

 .07 in. long; black, slightly bronzed; antennae and legs, 



373 



