1911] Aluttkoivslci, Studies in Tetragoneuria. P6 



TABLE OF THE SPECIES OF TETRAGONEURIA. 



A. Abdomen of male slender and parallel, a very slight constric- 

 tion at 3; length 30-33 mm., hind wing 29-32 mm. 



B. Wings without brown markings; thoracic stripes 

 black stella Williamson n. sp. 



BB. Wings with brown spots at antenodal intersections, 

 sometimes with spaces filled ; thoracic stripes metal- 

 lic, with violet reflections pet echialis n. sp 



AA. Abdomen of male spatulate, 3 distinctly constricted ; sides of 

 thorax rarely metallic, and only on sides below. 



B. Male appendages with tips widely separate, an inferior 

 angle at basal third, and a lateral ridge leading 

 beyond, no superior modification ; female append- 

 ages not exceeding 1.7 mm., vulvars flattened, divari- 

 cate. V-shaped, the tips divergent. 

 C. Color of hind wings not exceeding last ante- 

 cubital ; T-spot usually present, or indicated by 

 metallic reflection in median frontal sulcus ; 

 length abdomen rarely less than 28 mm. (28-32), 

 hind wing 28-32 mm. ; thoracic pile predomi- 

 nately gray. 

 D. Brown of hind wings reaching base of tri- 

 angle, or less cynosura Say 



DD. Brown of hind wings reaching tip of triangle 



and filling it, or more simulans n. n. 



CC. Color of hind wings reaching nodus ; T-spot 

 absent: length abdomen rarely more than 27 

 mm. (23-27, hind wing 24-26 mm.; thoracic pile 

 predominately brown semiaquea Burmeister 



BB. Male appendages with tips approximate, the inferior 



angle produced, no lateral ridge beyond angle, no 



superior modification ; female appendages longer 



than 1.7 mm., vulvars U shaped, the tips parallel. 



C. T-spot absent; small species, abdomen 29-31 mm., 



hind wing 31 mm.; female appendages 2 mm.; 



hind wing with streak to first antenodal 



wilHamsoni n. sp. 



