THE FIREFLIES OR LIGHTNING BUGS. 815 



apex mueh mure rounded aud hind angles less prominent than in 

 the next. 



1547 (4795). Piatekos canalictjlattjs Say, Bost. Journ. Nat. Hist., I, 



1835, 154 ; Ibid. II, 632. 

 Elongate, depressed. Black ; thorax with yellowish side margins ; ely- 

 tra with humeri sometimes reddish-yellow. Thorax with a narrow basal 

 chaimel extending almost to middle. Second joint of antennse minute, third 

 half the length of fourth. Length 5-8 mm. 



Throughout the State ; frequent. ^lay 10-July 27. Occurs on 

 leaves of milkweed and various shrubs. 



1548 (4798). Plateros floealis Melsh., Proc. Phil. Acad. Nat. Scl., II, 



1845, 302.- 

 Elongate, slender. Black, the side margins of thorax broadly yellow. 

 Antennie compressed, shorter and much less serrate than in Uctor. Tho- 

 rax with apex more broadly rounded and sides stralghter than in the next. 

 Length 5-6.5 nun. 



Throughout the State; frequent. June 2-Augusl; 11. Beaten 

 from vegetation. 



1549 (4797). Plateros lictoe Newm., Entom. Mag., V, 1838, 382. 

 Elongate, more slender than the preceding, with which it agrees in 



color. Antennse of male long, strongly serrate, third joint triangular, as 

 wide as long, fourth longer, not wider; those of female broader, less ser- 

 rate. Thorax subpentagonal, with the front margin raised and less broadly 

 rounded; the disk with an elongate channel on basal half, this extending 

 to middle in male, shorter and broader in female. Elytra with well marked 

 equal lines and more finely cross-barred interspaces. Length 5-7 mm. 



Throughout the State ; frequent. May 30-July 15. 



V. Calochromus Guer. 1833. (Gr., "beautiful -f- color. ") 



This genus is mainly distinguished by the pubescent velvety 

 surface and feebly striate, not reticulate, elytra. They have the 

 head ending in a short, broad beak; antennte rather widely sepa- 

 rated, subserrate, with joints thicker and less compressed; thorax 

 with an entire median groove, toward which a short, oblique ridge 

 runs from the middle of the thickened margin. 



1550 (4805). Calochromus PEKPACETrs Say, Amer. Entom., II, 1825, 4(;: 

 ibid. I, 46, pi. 21. 



Elongate, depressed. Black, velvety with fine pubes- 

 cence; sides of thorax broadly reddish-yellow. Antennse 

 with second joint one-third the length of third, the latter as 

 long but not as wide as fourth. Side margin of thorax im- 

 pressed at the middle, the basal lateral impressions deep. 

 Middle and hind tibise curved. Length 6.5-9.5 mm. (Fig. j,. gjg ^ ^ 



:J15.) (After Knobel.) 



[52—23402] 



