356 



PSYCHE. 



[June 1S90. 



pjgium black; lamellae large, elongate 

 oval, brownish yellow, posterior edges 

 black, irregularly crenulated and fringed 

 with weak black bristles; the numerous 

 smaller and moie concealed appendages 

 of the hvpopygium yellow. Coxae and 

 legs black throughout ; femora with a faint 

 metallic green reflection. Fore legs smooth, 

 tarsi equaling the tibiae in length ; median 

 femur with a preapical bristle, median tibia 

 with two setae on its posterior face, sepa- 

 rated by a distance equal to \ the length of 

 the tibia; hind femur with a preapical bris- 

 tle, hind tibia with four or five spines along 

 its posteriorface. Halteres pale dull yellow. 

 Wings smoky gray, becoming almost black 

 along the costal margin; veins black, the 

 third and fourth longitudinal veins gently 

 converging and, for a Gymnopternus, very 

 closly approximated at their tips. Anal 

 angle very obtuse, giving the wing a lance- 

 olate outline. 



Habitat : Milwaukee Co., Wis. 



Gymnopternus poenitens is to be ad- 

 mitted to the gi'oup comprising Loew's 

 G. scot las., G. barbattihis^ and G. 

 trtstis.1 all of which differ from the 

 other described North American spe- 

 cies of the genus in having the pre- 

 vailing color of the feet black. G. 

 poejtitens differs from G. scotias in 

 having the cilia of the inferior orbit 

 white, the feet entirely black, the hypo- 

 pygial lamellae large and in great part 

 yellow; from G. barbatiihis and G. 

 tristis^ G. poenitens differs in the 

 more hairy third antennal joint and 

 its completely black legs. Both of 

 Loew's species also have the cilia of 

 the inferior orbit black. The course of 

 the third and fourth longitudinal veins 

 is very different in G. poenitens from 



what it is G. tristis., in which species, 

 according to Loew, there is only a 

 slight convergency, though he men- 

 tions in a note a m;de with a "con- 

 siderably stronger convergenc}' of the 

 third and fourth longitudinal veins." 

 He considers this specimen to be 

 merely a striking variety of G. tris- 

 tis. 



Chrvsotus wisconsinensis, n. sp. J . $ . 



Length 2.5-2.75 mm. ; length of wing 2.- 

 2.25 mm. 



Splendid metallic green. Antennae en- 

 tirely black; third joint small, rounded, 

 rather hairy; eyes completely meeting on 

 the face in the male ; in the female the face 

 broad, covered with silvery white dust, and 

 crossed by a marked tran verse ridge a little 

 above the oral margin. Palpi black, small 

 and somewhat concealed in the male; con- 

 siderably larger and covered with silvery 

 white dust in the female. Front broad in 

 both sexes, triangular, widening towards 

 the occiput, metallic green, inclining to 

 violet, somewhat dimmed by a laver of fine 

 dust; cilia of the superior orbit black, 

 those of the inferior orbit glistening white. 

 Thoracic dorsum and scutellum bright 

 golden green, overlaid with a thin layer of 

 yellowish white dust, which is thickest on 

 the humeri : pleurae metallic green, rather 

 thickly covered with white dust, cilia of the 

 tegulae white. Abdomen bright golden 

 green, rather thickly covered witii black 

 hairs ; terminal segments moi^e blackish ; 

 hypopygium of the male quite large, barely 

 concealed, appendages glistening, black. 

 Legs quite hairy; fore coxae yellow, their 

 extreme bases metallic green in front; their 

 tips with a tuft of black hairs. Anterior 

 tarsi blackened from the tip of the second 

 joint; hind legs somewhat robust, tarsi 

 equaling the tibiae in length, black and 

 quite hairy, only the base of the metatarsal 



