INSECTS OF LOUISIANA. 309 



DILOPHUS Meig. 



D. stygius. — Black, polished ; inferior transverse wing ner- 

 vure distinct. 



Inhabits Louisiana. 



Body entirely black, immaculate, polished ; thorax with the 

 anterior series of spines slightly interrupted : wings dark fuli- 

 ginous, blackish on the costal margin; transverse [16] nervures 

 distinct; a darker shade on the stigma: anterior tibiae with a 

 series of spines on the middle and another at tip. 



Length to the tip of the wings about one-fourth of an inch. 



The ultimate cross nervure joins the middle nervure before the 

 bifid portion. The sexes are alike in their markings. This spe- 

 cies differs from the orbatus Wied., which is destitute of an ob- 

 vious ultimate cross nervure. 



[The name must be changed, as there is another Dilophus 

 stygius Say, Journ. Acad. Nat. Sci. Phil. 6, 155. I would take 

 the present to be a synonym of D. orbatus Say, if the sexes were 

 not here stated to be alike in their markings. — Sacken.] 



