162 Annals of the Carnegie Museum. 



CC. Costal side of stigma on the hind, and often also on the front, wing 

 shorter than the proximal or distal side, inferior appendages strongly up- 

 curved at tips, dorsum of 2 and of 7 black. truncatum. 

 BB. Pale postocular spots confluent with the pale color of the rear of the head ; 

 superior appendages with an anteterminal constriction in profile view, inferior 

 appendages but slightly, if at all, upcurved at tips, dorsum of 7 black. 



temporale. 

 A A. Superior appendages directed caudad, but not ventrad, curved up in the distal 

 half, projecting caudad twice as far as do the inferior appendages. 

 K. Each postocular spot one-third as wide as the distance from eye to eye, and 

 touching the eye-margin, second lateral thoracic suture with a short black 

 mark at its upper end only, dorsum of 2 chiefly blue with a triangular black 

 spot on its middle, dorsal black of 3-5 pointed anteriorly, 10 blue dorsally. 



char arum. 

 KK . P'ach postocular spot one-fourth to one-fifth as wide as the distance from 

 eye to eye and not touching the eye-margin, second lateral thoracic suture 

 with a black stripe reaching from the upper end two-thirds of the way down 

 to the metastigma, dorsum of 2 chiefly black with only a narrow transverse 

 basal blue ring, dorsal black of 3-5 almost rounded anteriorly, 10 black 

 dorsally. chacoense. 



2. Superior appendages distinctly shorter than the inferiors. 



L. Nasus and dorsum of prothorax black, a black humeral stripe (interrupted or not 

 interrupted superiorly), an interrupted black stripe on the second lateral thoracic 

 suture, abd. segs. 2 and 3 chiefly black, 2 with a posterior terminal transverse 

 pale band, 3 with a narrow basal pale ring, 8 and 9 blue with a lateral longi- 

 tudinal black stripe on each side. ( From de Selys' description. ) trimaculatum. 

 Nasus and prothorax entirely blue, a very short black line on the upper ends only 

 of the humeral and second lateral thoracic sutures, abd. segs. 2 and 3 chiefly 

 blue, 2 with an isolated transverse black stripe at three-fourths' length, 3 with 

 hindmost sixth black, 8 and 9 blue without black markings. ehirihuanum. 



Females. 



A. Postocular spots not confluent with the pale color of the rear of the head. 

 B. Black humeral stripe complete. 



C. Abdominal segments 9 and 10 (and in some also the hind end of 8) 

 blue, 9 with a basal black spot on each side. Size larger, abd. -3-27, 

 hind wing 17-18 mm. gracile, latapistyluvi. 



CC. Abdominal segments 9 and 10 black dorsally. 



D. Size larger (abd. 23, hind wing 16 mm.). gracile minarum, 



DD. Size smaller (abd. 19-20, hind wing 13—15 mm.). truncatum. 



BB. Black humeral stripe represented only by a short black line on the upper 



end of the humeral suture and a brown spot at its lower end, 8-IO as in 



gracile. gracile ablutum. 



AA. Postocular spots confluent with the pale color of the rear of the head, abd. segs. 



9 and 10 blue, 9 with a triangular basal black spot on each side, abd. 20-21, 



hind wing 14— 1 5 mm. temporale 



(The females of the other species are unknown.) 



