British Braconidw. 



27 



2nd cubital entirely effaced ; stigma triangular ; radial nervure 

 curved without an angle, effaced before reaching the tip of the 

 wing, it is however longer than in the genus Aphidius. Abdo- 

 men lanceolate, petiolate ; ventral valve of the 9 furnished with 

 two slender appendages or horns longer than the terebra, curved 

 upwards at the extremity ; 1st segment linear, the spiracular 

 tubercles variously placed. Terebra directed somewhat downwards, 

 as in Monoctonus. 



The females may be distinguished at a glance by the 

 armature of the abdomen ; the males may be easily mis- 

 taken for such of the genus Aphidius as have the 1st 

 cubital areolet indistinct, but in the latter the radial ner- 

 vure is shorter, the antennae have usually more articula- 

 tions, and the form of the stigma is generally narrower. 

 Ten species of Trioyys have been described belonging to 

 the European fauna, and a greater number in America. 



Table of Species. 



I have found it impossible to tabulate some of these species in a satisfac- 

 tory manner, partly for want of specimens, and partly (as in the case of the 

 three last,) on account of defective descriptions. 



(2) 

 (1) 

 (4) 

 (3) 

 (6) 



(5> 



(8) 



(7) 



(10) 



(9) 10. 



(12) 11. 



(11) 12. 



(14) V6. 



(13) 14. 

 (16) 15. 



(15) 16. 

 (18) 17. 



(17) 18. 



Antennse 12-iointed 



Antenna; witli fewer than 12 joints 



Antennre with 11 joints 



Antennie with 10 joints 



Antenna; progressively incrassated from 

 base to ape.'c 



Anteunje filiform 



Face testaceous 



Face black ; only the oral parts pale 



Intermediate segments of the abdomen 

 fuscous; the posterior yellow (1st 

 segment dull testaceous) 



All the segments black, escej)t the 1st, 

 which is clear yellow 



Spiracles of the 1st segment situated 

 behind the middle 



Spiracles situated in the middle 



Appendages of the ventral valve in the 

 9 black. Length, 1 line 



Appendages of the ventral valve in the 

 9 testaceous. Length, \ line 



Last joint of the antenna; soldered to 

 the preceding, and hardly dis- 

 cernible 



Last joint of the antenn.-e free 



Abdomen pale yellow, the intermediate 

 segments, and sometimes the pos- 

 terior, infuscated 



Abdomen indistinctly yellowish an- 

 teriorly ; 1st segment infuscated in the 

 middle 



1. (met us, Hal. 



3 

 5 



2. Ircvicornis, Hal. 



7 

 11 



3. luraclci, Hal. 



9 



4. accn'.i, Hal. 



5. hcti'Lv, Marsh. 



15 

 13 



6. ccntai'reie, Hal. 



7. angelica^, Hal. 



8. minnti's, Hal. 

 17 



9. 2^('Ui^l"f, Hal. 

 10. letifer, Hal. 



