Wasps of the Genus Tachytes. 



Black; the apical margins of the abdo- 

 minal segments brown T. observaliliii, Kohl, 



9. Wings black, flushed with blue ; or dark 



fusco-hyalina 10. 



Wings hyaline, subhjaline, or flavo- 

 Lyaline, sometimes pale fusco-hyaline 

 at the apex 13. 



10. Wings dark fusco-hyaline, abdomen with 



interrupted fascife of silver pubes- 

 cence T. mcBrens, Turn. 



Wings black, flushed with blue or 

 purple 11. 



11. Front and clypeus clothed with long 



black hairs T. nigropilosella , Cam. 



Front and clypeus with short sericeous 

 pubescence 12. 



12. Pubescence of front and clypeus silver ; 



anterior tibite black T. natalensis, Sauss. 



Pubescence of front and clypeus golden; 



anterior tibiae ferruginous T. memnon, Turn. 



13. Abdomen black, without pubescent 



fasciae T. nudiventris, Turn. 



Abdomen with pubescent fasci;e 14. 



14. Abdomen densely covered with silver 



pubescence ] 5. 



The pubescence, if silver, re.stricted to 

 the apical fasciae on the dorsal seg- 

 ments 17. 



15. Basal joint of fore tarsus with five 



spines T. distanti, Turn. 



Basal joint of fore tarsus with .six spines. 16. 



16. Clypeus subtruncate at the apex ; 



pygidial area clothed with golden 



pubescence T. aryenteovestita, Cam. 



Clypeus rounded at the apex; pygidial 

 area clothed with reddish brown 

 setse T. huluwayoensis, Bisch. 



17. Two basal abdominal segments at least 



red 18. 



Basal abdominal segments black 19. 



18. Three basal abdominal segments red ; 



clypeus without prommeut teeth ; 

 apical slope of median segment closely 



transversely striated T. sjostedti, Cam. 



Two basal abdominal segments red ; 

 clypeus with two prominent teeth : 

 apical slope of the median segment 

 closely and minutely punctured .... T. arnbideyis, Kohl. 



19. Wings tiavo - hyaline, fusco - hyaline 



apicaliy from the second cubital cell ; 

 pubescence of abdomen dense and 

 golden ; sparse golden pubescence on 



the sides of the mesonotum T. dilaticornis, Turn. 



Wings, if tiavo-hyaline, without a broad 

 fusco-hyaline margin 20. 



20. Galea very long, more than twice as 



long as the scape 21. 



