iy6 ASHMEAD 



Abdomen with second suture including the extreme apex of the second 

 segment and the apex of the third segment, testaceous (sometimes 

 with only the second and third sutures testaceous); second joint of 

 flagellum a little shorter than the first, the following imperceptibly 

 shortening the penultimate joint being only a little longer than thick. 



B. imitator. 



17. Antennae 22-jointed or less 18. 



Antennae 23-jointed. Male. (Female 19-jointed.) 

 Abdomen with the third segment dark rufous B. simillima. 



18. Antennae 21-jointed or less 19. 



Antennae 22-jointed. Males. (Female i8-jointed.) 

 Abdomen with the extreme apices of the second and the third segments 



testaceous B. confusa. 



Abdomen with the apex of the second segment and the third entirely 

 testaceous B. co7tfusa. 



19. Antennae 20-jointed or less 20. 



Antennae 21-jointed. Female. 



Abdomen with the apex of the second segment, second suture and the 

 third segment basally, testaceous B. ungcB. 



20. Antennae 19-jointed or less 21. 



Antennae 20-jointed. 



Females. (Male 24-jointed.) 



Abdomen with base of second segment and the third 



more or less dark rufous. 

 Length 4 mm. Metathoracic areola horse-hoof shaped ; areolet 

 receiving the second recurrent nervure before its apical third. 



B. rtibrocincta. 

 Length 3 mm. Metathoracic areola hexagonal ; areolet receiving 



the second recurrent nervure at its apical third B. imitator. 



Males. (Female unknown.) 



Length 3.5 mm. Third and fourth antennal joints equal, both a 



little longer than the fifth B. quadriceps. 



Length 4 mm. or more. Third antennal joint a little shorter than 

 fourth, but equal to the fifth B. simulator. 



21. Antennae 19-jointed. Female B. simillima. 



Antennae i8-jointed. Female B. confusa. 



22. Antennae 21-jointed or less 23. 



Antennae 24-jointed. Male. 



Abdomen black, with dorsal segments 2 and 3 red, and sometimes the 

 apex of the first and the base or more of the fourth, red... ,5. bicolor. 



23. Antennae 21-jointed. Male. 



None in this section known from Alaska. 

 Antennae 19-jointed. Female. (Males 23-jointed.) 

 None in this section known from Alaska. 



