208 COLEOPTERA OF NORTH AMERICA. 



Grroup IV. — Luciolae. 



The eyes are large, convex, and widely separated above and 

 beneath in both sexes, not conspicnously larger in the %; the 

 head is rounded, narrowed behind and not retractile ; it is but 

 partially covered by the prothorax, which is, however, of the 

 usual hood-like form and ronnded in front. The antennae are 

 longer than one-half the body, filiform, slender, not compressed, 

 inserted near the anterior margin of the front, and moderately 

 approximate; the second and third joints are about equal, and 

 together are as long as each of the following joints. 



The sexes are similar in form with long elytra and well de- 

 veloped wings; the light organs occupy the whole of the fifth and 

 follow'ing segments ; stigraa-likc pores are not obvious, being 

 situated at the base of the fifth and sixth segments and less 

 strongly marked than in Pyractomena and Photinus Z . The 

 seventh ventral in 9 is obtusely triangular; in % the fifth and 

 sixth are broadly craarginate, the seventh is smaller than in 9, 

 sinuate at the sides and prolonged at the middle, the eighth is a 

 little wider and longer than the prolongation of the seventh. In 

 our species the outer (or anterior) claw is cleft at tip. The pro- 

 thorax and elytra are densely rugosely punctured, the former is 

 yellow with a black stripe or spot, each side of which the disk is 

 red; the latter have the whole margin and frequently a discoidal 

 stripe pale. A single genus, Photuris, occurs in our fauna with 

 limited representation in the Atlantic region. 



Trihe II.— PHE>"GODIXI. 



The prothorax though rounded in front does not cover the 

 head, which is exposed. The eyes are convex, prominent, and 

 widely separated; the antennae are not approximate, inserted in 

 front and inside of the eyes, and are plumose or flabellate in the 

 %; (9 unknown, except in Tytthonyx, where it is similar to 

 the %). The nmndibles are long, slender, and curved, the labrum 

 connate with the front, small in Pterotus, large and emarginate 

 in Phengodini ; the middle coxse are contiguous, the metasternum 

 between them being narrowly carinate. The gula is deeply- 

 impressed or excavated in all the genera. 



Three sub-tribes are indicated : — 



