510 



Adults of this species have been taken at Oregon in Ogle County, 

 at Mahrimet in Champaign County, and at Muncie and Oakwood in 

 \'erniili(in County, liut the species is not especially ahinidant in any of 

 these localities. The nymphs are reported by Ncedham ('03) as living 

 under stoi\cs in swift currents and by Kellicott ('99) as living on the 

 piles of docks in Lake Erie. 



Argi.x sedul.v (Hagen) 



Nyiiipli. — Unknown. 



Adult; J/u/r.— Color, blue and black. 



Head black and l)lue, tlie labium pale blue and buff: palpi narrow, 

 the second segment d-'irk and shorter than the fi.xcd hook, the cleft of 

 the median lobe obtuse at the base and shallow ; postclypeus pale except 

 a black transverse stripe along the dorsal margin; anteclypeus, labrum, 

 exposed portions of the manilibles, a transverse area above the clypeus, 

 and a spot latero-cephalad of each antenna l:)lue ; lateral ocelli w-ith small 

 yellow spots laterad of each, the remainder of the front and vertex 

 being black ; postocular blue spots large and contiguous with the mar- 

 gins of the compound eves; occiput and postgenac, with the exception 

 of rather narrow black stripes caudad of each postocular spot, yellow- 

 ish buff. 



Tiiorax : pronotum largely black, the median lobe with large sub- 

 circular spots and the caud.d lolje willi a pale spot on the extreme 

 lateral angles, I)lue: proepimera and episterna blue; mesostigmal plates 

 subtriangular, not j)rojecting caudad; dorsal carina of tlie mesothorax 

 covered liy a broad lilack strijie which also covers about one-half of 

 each mesepisternum and is followed l)y a broad l)lue stripe which cov- 

 ers the rest of the mesepistema ; the blue mesopleural stripe is wider 

 adjacent to the mcsostigma and is gradually narrowed caudad; the 

 mesopleural suture is covered by a broad lilack stripe which also covers 

 most of tlie mesepimera except the cephalo-\entral shoulders, and is 

 considerably widened adjacent to the wing bases, enclosing a small blue 

 spot ; ventral lialf of the mesinf racpisterna yellow, the remainder black ; 

 mctapleural suture witli a narrow black line from wing liases to the 

 metathoracic sjiiracles; rem.'iinder of the pleura and the postcoxal areas 

 pale blue or l)uff ; legs ])lue and black, the coxae pale, the trochanters 

 black above, the femora black above and pale below, the front femora, 

 however, with more or less bl;ick between tlie rows of setae ; liliiae black 

 below, pale above; tarsi dark brown, the claws bifid at the tip; wings 

 with twelve to fourteen postnodal cross-veins in the front wing and 

 eleven to twelve in tlic bind ; ]\L. arising between the sixth and seventh 



