CARABID^. 



433 



of use as a protection against its enemies. They are yellow- 

 ish red, with bluish and greenish elytra. Helluomorpha 

 (H. ,prseusta Lap. Fig. 369 ; a, mentum) has a 

 large mentum and much compressed antennae. 

 Galerita is similar but 

 much larger, with a red 

 thorax, and blue or black 

 elytra. Fig. 370 represents 

 the larva ; Fig. 371 the pupa Fi s- 

 of G. Lecontei Dejean, a Southern species. 

 Casnonia has a rhomboidal head, with 

 a long narrow neck and a cylindrical tho- 

 rax. C. Pensylvanica De- 

 jean (Fig. 372) is not un- 

 common, being found 

 under stones. The species 

 of Lebia are found upon^ 

 flowers, especially the 

 golden rod, in August and 

 September. They are gaily 

 colored, with the head con- 

 stricted behind and the Fig. 371. 

 thorax pedunculate. The species of 

 Platynus (P. cupripenne Say, Fig. 373) 

 are often of brilliant metallic green and red colors. In Cymin- 

 dis, which is hairy, the head is not constricted behind, and the 

 last joint of the labial palpi is dilated. In Pterosti- 

 chus, which is a genus of great extent, the three basal 

 joints of the antennae are smooth, the 

 J anterior tibiae are thickened at the ex- 

 J tremity, and the dilated tarsal joints are 

 triangular or cordate. The species are Fig. 372. 

 black and of common occurrence. Amara differs 

 in the head not being narrowed behind, the slightly 

 Fig. 373. emarginate labrum and the elytra being without 

 the usual punctures. Zimmerman states that the species are 

 annual, or double brooded annually ; the eggs, which are laid 

 beneath the surface of the soil, do not mature for several 

 days after coupling ; the larvae moult once, live six to eight 

 28 



