THE GROUND BEETLES. 



41 



Common throughout the State. April 23-September 5. Some- 

 times occurs under rubbish remote from water. 



20 (77). Omophrow tesselattjm Say. Journ. Phil. Acad. Nat. 

 ScL, III, 1823, 152; ibid. II. 07. 



Pale brownish-yellow ; bead with a green band across the 

 base; thorax with a small, subquadrate green spot which is 

 prolonged backward and forward along a deeply impressed 

 median line ; elytra with cross-markings metallic green, the 

 punctures of the striae close and fine. Thorax coarsely punc- 

 tured near base and apex, more finely and very sparsely at middle and 

 sides. Length 6-7 mm. (Fig. 28.) 



Common in the northern part of the State ; rare in the southern 

 portion. May 22-August 22. 



Tribe II. CYCHKIXI. 



Head more or less constricted ; neck often semi-globose ; an- 

 tennae slender, inserted under a feeble frontal ridge ; labium deep 

 ly forked ; body not pedunculate ; seutellum very small. Prester- 

 num not prolonged behind the coxae ; hind coxae separated by a tri- 

 angular process of the abdomen. The tribe is represented in the 

 eastern United States by two genera, separated as follows : 



KEY TO GENERA OF CYCHKIXI. 



a. Antennae with four basal joints glabrous. II. Cychrus. 



aa. Antennae with two basal joints glabrous. Nomaretus. 



Of these only specimens of Cychrus have as yet been taken in 

 Indiana, though two or three species of Nomaretus should be found 

 here. They are black or violaceous in color and 10-13 mm. in 

 length, 



II. Cychrus Fab. 1794:. (Or., "a ground runner.") 



Beetles of medium or large size, violaceous or brownish-purple 

 in color, having the head elongate, the mandibles long, slender, 

 curved and without a bristle-bearing puncture on the outer side ; 

 labial and maxillary palpi very long, the last joint hatchet-shaped 

 and concave. The elytra have 14 to IS very distinct striae, which 

 are sometimes irregular or replaced by tubercles. The species live 

 beneath stones and leaves, usually in moist woods, and feed upon 

 snails, their long; heads having, in the course of time, become especi- 

 ally adapted to extracting these animals from their shells. For 

 synopses of the genus see: 



