PARASITICA CYNIPIDJE. 31 



foveae; metathorax with two straight, parallel, longitudinal ridges; 

 ventral spine, at most, scarcely twice as long as thick ; marginal cell 

 closed; claws of posterior tarsi distinctly or indistinctly bidentate...l9. 



Abdomen with the second and third segments not united 20. 



19. — Antennw with 12 free joints, the third shorter, or at most as long as fourth, 

 flagellum filiform ; prothorax with two more or less distinct carinulue, 

 converging above (backwards) ; niesothorax finely alutaceous punctate 

 and hairy, or (as in P. gylventris O. S.) very finely and feebly alutaceous ; 

 claws of posterior tatsi bidentate: (in galls of Rubus and Roxa). 



9. Periclistus Forst. 



Autennse 13-jointed, the third very distinct, longer than fourth, apical joint 

 thicker than the middle of the antennse; prothorax without trace of a 

 ridge extending upward ; mesothorax sharply transversely wrinkled ; 

 claws of posierior tarei bidentate ; (in African Rhus-gaUs). 



10. -sRhoophilus Mayr. 

 20. — Base of scutellum with an uninterrupted groove not externally closed ; mar- 

 ginal cell short and completely closed ; cheeks more than half as long as 

 the eyes; antennse with 13 free joints; prothorax not narrowed me- 

 dially ; parapsidal grooves absent on anterior third of mesothorax, which 

 is sharply alutaceous i)unctate and opaque; claws of posterior tarsi en- 

 tire; (in Centaurea stalksl 6. *Phanacis Forst. 



Base of scutellum either with an externally closed transverse groove or with 



two fovese 21. 



21. — Scutellum with a very distinct, excavated, longitudinal, wrinkled furrow; 

 cheeks at least half as long as the eyes ; apical third of the 13- (or 14?) 

 jointed antennae not thicker than the middle; head and thorax (espe- 

 cially the mesothorax) and scutellum, veiy deeply wrinkled and hairy; 

 mesothorax with two distinct or indistinct, not polished. para])sidal 

 grooves ; base of scutellum with niotlerately deep subquadrate fovea>, 

 the disc somewhat broader than long, obtusely rounded posteriorly and 

 in middle an entire longitudinal groove; marginal cell entirely open at 

 the wing margin, very brown or pale brown at base ; claws of jH)stericr 

 tarsi bidentate ; (in N. Am. Oak-galls) 16. Amphibolips Eeinh. 



Otherwi.se formed ; scutellum without a distinct longitudinal groove (except 



in a species of Aular, in which the claws are entire) 22. 



"22. — Cheeks more than half as long as the eyes and without furrow ; flagellum 

 filiform, the apical third not thicker than joints 5-6; head not or .scarcely 

 wider behind the eyes; prothorax not narrowed medially, or at least 

 - not strongly constricted : parapsidal grooves entire ; l)ase of scutellum 

 with two sharply impressed fovea ; ventral spine, at most, a little longer 

 than thick 23. 



Cheeks, at most, half as long as the eyes; antennae with apical third thicker 

 than joints .5-6 ; prothorax small, or very small ; marginal cell elongate 



and open at the wing margin 2.5. 



'£i. — Claws of posterior tarsi bidentate ; mesothoi-ax polished, in D. potenfillge 

 Bass., nearly polished ; (in gi.Us of Rubus ;iud Potenfilln). 



1,'j. Diastrophus Hartig. 



Claws of posterior tarsi entire ; mesothorax with distinct sculpture, except 

 in Anlax, where it is often more or less polished 24. 



