THE FIREFLIES OR LIGHTNING BUGS. 



829 



truncate or even somewhat emarginate in front; seventh ventral 

 segment of male truncate, the eighth exposed. The tarsal claws of 

 all our known Indiana species are armed with a long acute tooth, 

 causing them to appear broadly cleft. In another group, which 

 may yet be found to be represented in the State, the claws are 

 armed with a broad, nearly rectangular, basal tooth. Eight spe- 

 cies have been taken in the State. 



KEY TO INDIANA SPECIES OF PODABRUS. 



a. Eighth ventral segment of male triangular, flat, rounded at tip. 



1). Elytra distinctly dilated on the sides, their elevated lines strongly 

 marked ; antennae stouter. 



c. Size larger, 11-13 mm. ; thorax more than twice as wide as long. 



1574. TRICOSTATUS. 



GO- Smaller, 7-8 mm. ; thorax not much wider than long, distinctly 

 narrowed in front. 1575. rugosulus. 



bb. Elytra not or scarcely dilated on the sides, their elevated lines in- 

 distinct. 



d. Elytra rather coarsely rugose. 



e. Thorax twice wider than long ; color smoky brown or dull black. 



1576. BASILARIS. 



ee. Thorax but little wider than long ; color, except sides of thorax, 

 shining black. 1577. frater. 



del. Elytra finely rugose; thorax but little wider than long. 



/. Elytra black without pale margins ; median impressed line of 

 thorax distinct. diadem a. 



ff. Margins and suture of elytra narrowly pale ; median line of tho- 

 rax feeble or wanting; second and third joints of antenme sub- 

 equal. 1578. modestus. 

 aa. Eighth ventral of male oblong with sides parallel, obtusely rounded at 

 tip. 



g. Head suddenly narrowed behind the eyes, neck short ; head and tho- 

 rax uniform reddish-yellow. 1579. tomentoses. 

 gg. Head much prolonged behind the eyes, neck long. 



Ti, Head sparsely punctured behind ; thorax feebly punctured. 



15S0. PROTENSUS. 



hh. Head and thorax both coarsely, the latter sparsely punctured. 



1581. BRUNNICOLLIS. 



1574 (4879). Podabrus teicostatus Say, Bost. Journ. Nat. Hist., I, 1835, 

 158 ; ibid. II, 635. 

 Elongate, robust. Black ; front of head and sides of tho- 

 rax reddish-yellow. Antenna? about half the length of body, 

 joints two to four increasing in length. Head and middle 

 of thorax densely punctured, the sides of latter broadly flat- 

 tened and reflexed. Elytra very broadly dilated on middle 

 third, densely rugose, each with three strongly elevated lines. 

 Male elytra less dilated and antennae longer than in female. Fig. 323. x li 

 Length 11-13 mm. (Fig. 323.) (After Knobel.) 



Lawrence and Perry counties; rare. May 31- June 17. 



