ACKIDID^3. 651 



wilh two smooth calli on each side and with distinct transverse impressed 

 lines; fore border, sides and hind border rounded. Prosternal spine 

 slender, acute, slightly compressed. Hind femora much longer than the 

 abdomen; hind tibiae much shorter than the hind femora. Fore wings 

 narrow, a little shorter than the body. 



1. SYNTOMACKIS VITTIPENNIS. 



Mas. Testacea ; vertex nigricante bistrigalus ; frons piceo bivillala ; 

 palpi pallide virides ; antenna rufce, bad nigricantes ; prothorax 

 nigro trivittatus ; abdomen piceo univittatum ; pedes nigri, femoribus 

 posticls testaceis apice nigris, tarsis pallide viridibus ; alee anticce 

 nigricantes, testaceo bivittata ; alee poslicce cinerece, fusco mar- 

 ginatcs. 



Male. Testaceous. Vertex with two blackish streaks, which are 

 united in front; front with two piceous stripes. Palpi pale green. Eyes 

 lurid. Antennae very bright red, blackish at the base. Prothorax wilh 

 three black stripes. Abdomen with a piceous stripe. Legs black; hind 

 femora testaceous, black towards the tips; tarsi pale green. Fore wings 

 blackish, with two pale testaceous lanceolate slripes. Hind wings cine- 

 reous, brown along the border; veins black. Length of the body 7 lines ; 

 expansion of the fore wings 15 lines. 



a. Nauta, Amazon Region. From M. Degand's collection. 



Genus 23. STENACRIS. 



Mas. Corpus gracillimum, fere cylindricum. Caput longum ; fasti- 

 gium conicum ; frons valde retracin, carinis quatuor bene determinatis. 

 Oculi obliqui, subprominuli. Antennae filiformes, gracilHtnse, prothorace 

 longiores. Prothorax subtiliter punctatus, non carinatus ; margines sub- 

 rotundati. Prosterni spina robusta, ohliqua, apice rotundata, mesosternum 

 non attingens. Abdomen compressum, lanceolatum. Ala? anticse angusta?, 

 corpore vix breviores. 



Male. Body shining, very slender, nearly cylindrical. Head elon- 

 gate, smooth, with a transverse furrow between the eyes ; tip of the vertex 

 conical; front much retracted, with four distinct keels; inner keels 

 parallel, approximate; outer keels diverging towards the face. Eyes 

 oblique, elongate-elliptical, slightly prominent. Antennae filiform, very 

 slender, longer than the prothorax. Prothorax finely punctured, not 

 keeled; transverse impressed lines slight; fore border, sides and hind 

 border slightly rounded. Prosternal spine stout, oblique, rounded at the 

 tip, not extending to the mesosternum. Abdomen compressed, lanceolate. 

 Hind femora as long as the abdomen ; hind tibiae much shorter than the 

 hind femora. Fore wings narrow, nearly as long as the body. 



1. STENACRIS LANCEOLATA. 



Mas. Pallide testacea ; antennce picece, basi teslacea ; abdomen villa 

 dorsali nigricante lanceolata; tarsi poalici pallide rufi ; alee antics 

 dimidio apicali diapkance. 



