1865.] 345 



Areolet very indistinct ; % 0.14 long 25. C. coelebs O. S. %. 



(Q. rubra?) 

 7. Areolet present (the veins, bounding it on the inside may often be 



nearly obsolete, still the areolet, in a certain light, is visible.) S 



No areolet 25 



■S. Mesonotum and scutellura clothed with a rather dense, apjjressed 



pubescence ;i 



Mesonotum altogether glabrous or seldom with a few short, scat- 

 tered, microscojdc hairs* 13 



9. Body reddish, small (0.10—0.12 long) ( 4 C. tubicola S. 9. 



J { (Q. obtusiloba.) 



Body black or brown ]<\ 



10. Posterior half of the abdomen pubescent I l " Ct strobilana O. S. 9 . 



r { (Q. bicolor ?) 



Posterior half of the abdomen not pubescent 11 



, , n j ,1 A no 1 f 5. C. clavula Bassett in 



11. Body not more than 0.12 long j lltt . ? . (Q alba-) 



Body more than 0.15 long 12 



12. A brown cloud in the anarle between the radial ") „ _ . . , » ,. _ 



j 1 -i 1 j if 11 ' ... C. centricola U.S. 9 . 



and cubital veins and a couple of irregular brown :■ ,zr -r* ., , ' * 



mark, towards the apex of the wing. j ^- obtusiloba.) 



No clouds or marks in the space between the ra- ( 2. C. globulus Fitch 9 ■ 

 dial and cubital veins J (Q. alba.) 



13. Mesonotum more or less distinctly, (although sometimes microsco- 

 pically) sculptured 14 



Mesonotum smooth, shining, without any apparent sculpture (ex- 

 cept the usual longitudinal furrows) 23 



14. Sculpture of the mesonotum very coarse and rough 15 



Sculpture of the mesonotum delicate 10 



15. % Antenna? distinctly 16-jointed : 9 hind feet") 27. C. singularis Bas- 

 concolorous with the other feel, reddish; 9 a °- \ sett % 9- 

 domen red or reddish-brown J (Q. rubra.) 



.. . , , . . • , , , . , e i 1 1 iu ( 28. C. Osten-Sackenii 



% Antennre 15-jomtea; 9 hind teet darker than ] Raq<= P tt t O 



the two other pairs, brown; 9 abdomen black.! ,q j 1 ; 7. ; ^-, 1 ; ^ 1 



16. The whole pleurae are rugose, opaque 17 



A considerable portion of the upper part of the pleurae is smooth 



and shining 21 



17. 9 Antennce distinctly 15-jointed ; whole body ( 9 ) n °t black nor 



dark brown IS 



9 Antennae 13 or 14-jointed ; body (except antennas or feet) black 



or dark brown 19 



IS. 9 head and thorax brownish-yellow, abdomen I 37. C. ventricosa Bas- 

 brownish | sett 9- (Q. ilicifolia.) 



9 bead and thorax deep-black, abdomen bright [ 29. C. formosa Bassett 

 red J 9 . (Q. rubra.) 



19. Mesonotum with a dense, even sculpture, giving it a handsome, 



semiopaque appearance 20 



Mesonotum rather shining, its sculpture percep- ) 38. C. cornigera O. S. 9 • 

 ceptible under a very strong lens only J (Q. palustris.) 



* The only possible error here is with C. jictiolicola, which may be referred to 

 the preceding diagnostic phrase, as its thorax has a sparse, but rather distinct 

 pubescence. 



