THE FIREFLIES OR LIGHTNING BUGS. 



819 



A well-marked variety of corrusca taken by Wolcott near 

 Clarke, Lake County, and by myself in Steuben County; scarce. 

 May 25-June 12. 



1555 (4815b). Ellychnia lacustris Lee, Proc. Phil. Acad. Nat. Sci., V, 



1851, 334. 



Elongate-oblong, narrow, parallel. Dull sooty-black. Thorax semi- 

 elliptical, its edges only indistinctly paler and sparsely punctate. Elytra 

 finely granulate, with one costa only fairly distinct, the others obsolete. 

 Length 5 mm. 



Lake County; rare. July 2. Smaller and much narrower than 

 autumnalis and probably a distinct species, though classed as a 

 variety of corrusca by LeConte in his Synopsis. A northern form 

 described from the Lake Superior region. 



IX. Pyropyga Mots. 1853. (Gr.. " fire 4 rump.") 



Rather narrow forms, having the antennae moderately wide and 

 compressed, with second joint transverse, one-third as long as third, 

 the latter in our species longer than fourth ; last dorsal segment in 

 both sexes broadly truncate with rounded angles ; segments lobed at 

 the sides, with the angles but feebly produced backwards ; light 

 organs but slightly developed. 



KEY TO INDIANA SPECIES OF PYROPYGA. 



a. Thorax with black disk and narrow piceous or dusky edges. 



b. Elytra costate ; length 6.5-8 mm. 1556. fenestralis. 



6&. Elytra not costate; length 4.5-6 mm. 1557. nigricans. 



a a. Thorax with black disk and reddish-yellow sides. 155S. decipiens. 



1556 (4817). Pyropyga fenestralis Melsh., Proc. Phil. Acad. Nat. Sci., II, 



1845, 304. 



Elongate-oval, slender. Black or blackish-brown ; thorax with a large 

 reddish-yellow subtriangular space on each side of the black central disk. 

 Elytra finely granulate and with two or three rather indistinct costa?. Length 

 6.5-8 mm. 



Laporte. Steuben. Marshall and Yigo counties; frequent. June 

 ID-August IT. Taken by sweeping grass and low herbage, usually 

 in moist meadows. 



1557 (4818). Pyropyga nigricans Say, Journ. Phil. Acad. Nat. Sci., Ill, 



1823, 179 ; ibid. II, 116. 

 Resembles the preceding in form and in color of thorax. Differs mainly 

 in its smaller size and lack of raised lines on elytra. Length 4.5-6 mm. 



Steuben. Starke and Marshall counties ; frequent about tam- 

 arack marshes. June 17-JuIy 15. 



