PTEROMALIDAE OF N.W. EUROPE 



515 



(2) Oral fossa extremely wide, reaching nearly to the eyes, its breadth 1 1 to 34 times 



the malar space. Base of mandible separated from edge of gena by a large 

 subcircular pit (Text-fig. 338) which is membranous at the bottom. Ocelli 

 moderate-sized, the posterior ones separated by about twice their major 

 diameter from the eyes ......... 



Oral fossa not nearly reaching the eyes, its breadth at most 4-3 times the 

 malar space. Usually there is no large subcircular pit between base of 

 mandible and gena, but if such a pit is present then the ocelli are small, the 

 posterior ones separated by about three times their major diameter from the 

 eyes ............. 



(3) Head in dorsal view with temples converging strongly and only one sixth as 



long as the eyes or less ; the head relatively more transverse. POL greater 

 than OOL. Fore wing with postmarginal vein nearly 1-5 times as long 

 as the marginal vein ; the latter equal in length to, or slightly shorter than, 

 the stigmal vein ...... P. bifoveolatus Forster (p. 



Head in dorsal view with temples converging only slightly and about one third 

 as long as the eyes ; the head relatively less transverse. POL hardly 

 greater than OOL. Fore wing with postmarginal vein only slightly longer 

 than the marginal vein ; the latter slightly longer than the stigmal vein 



P. squamifer Thomson (p. 



(3) Base of mandible separated from gena by a large subcircular or semicircular 



membranous area. Oral fossa large, its breadth 2-5 to 4-3 times the malar 



space. POL about equal to OOL ; posterior ocelli small, separated by about 



three times their major diameter from the eyes ..... 



490) 



49i) 



420 



Figs. 417-421. Habrocytus and Pteromalus spp., <$. 417, H. berylii (Walker), $, head ; 

 418, H. elevatus (Walker), q", head ; 419, H. cioni Thomson, q\ head ; 420, P. venustus 

 (Walker), $, head ; 421, H. dolichurus Thomson, <$, scape of right antenna. 



