XVI 



INTRODUCTION. 



nised by the tuberculate or obliquely incised abdomen, though these fea- 

 tures fail us in several groups to such an extent that even Gravenhorst des- 

 cribed several of the males under the Tryphoninae and no good definition 

 has yet been enunicated by which to distinguish therefrom males of the 

 present sub-family, which have no abdominal modification. The females 

 are readily and at once conclusively known by their sessile abdomen and 

 exserted terebra ; the sole exception occurring in the genus Banchus, 

 which cannot, however, be separated in general structure far from Exe- 

 tastes, in which the terebra is very distinctly protruded ; hence the Ban- 

 chides lead up naturally to the Tryphoninae and, indeed, were therein 

 placed by Thomson. 



(9). 



A TABLE OF FAMILIES OF 

 THE ICHNEUMONIDEA (PARASITICA). 



Abdomen emitted from the metanotum . . 

 Abdomen emitted from the apex of meta- 



thorax. 

 Front wings with discoidal nervures. 

 Terebra rising from near apex of the 



usually deplanate abdomen. 

 Front wings with two recurrent nenaires 

 Front wings with one recurrent nervure 

 Terebra rising from near base of the 



usually compressed abdomen 

 Front wings with no discoidal nervures. 

 Prothorax not reaching base of wings ; 



venter emitting terebra 

 Prothorax reaching base of wings ; anus 



emitting; terebra 



EVANIIDAE. 



ichneumonidae. 

 Braconidae. 



Cynipidae. 



Chalcididae. 

 Proctotrypidae . 



A TABLE OF SUB-FAMILIES OF THE ICHNEUMONIDAE. 



(4). 



(3). 



First segment basal ly contracted ; areolet 

 pentagonal. 



Mesosternum not sulcate ; terebra con- 

 cealed 



Mesosternum sulcate ; terebra exserted. , 



First segment not pctiolate nor areolet 

 pentagonal. 



Abdomen dorsally deplanate ; postpetiole 

 broad. 



Metanotum rarely longitudinally costate ; 

 terebra exserted 



Metanotum usually longitudinally costate; 

 terebra concealed. 



Abdomen laterally compressed ; post- 

 petiole linear , , 



Ichneumoninae. 

 Cryptinae, 



Pimplinae. 



Tryphoninae. 



Ophioninae, 



