Pomona College Journal ok Entomology 423 



Synopsis of the Genera of Triozinae 



A. Radius longer than basal portiDii cif sulicosta. 

 B. Facial cones (as cones) entirely wanting or siilt-uljsulctc. 

 C. Vertex very deeply eniarginate anteriorly at median suture, with the- 

 antennic attached to the projecting rostra. Facial coiks entirely 

 wanting. 

 D. Hi-rostrate appearance of head very marked; cmargination very deep. 

 Third antennal segment not very thick midway, sometimes some- 

 what eidarged. Rhiiwpsylla Riley 

 UD. Bi-rostrate appearance of head not so conspicuous, emargination 

 deep but less than above. Third antennal segment very much en- 

 larged and thickened midway, thicker than succeeding segments 

 and almost as thick as preceding. Bactcriccra I'uton. 

 CC. Vertex not deeply emarginate anteriorly, without the peculiar bi- 

 rostrate appearance. Facial cones sub-obsolete, with merely globose 

 projections at insertion of antennae. Epitrioza Crawford. 

 BB. Facial cones (as cones) not entirely wanting. 

 C. I'ronotum long, quite flat, not depressed below dorsulum and heail ; 

 dorsulum not strongly arched. Allot rioca Crawford. 

 CC. I'ronotum short, arched and distinctly descending cephalad ; distinctly 

 depressed below dorsulum and head ; dorsulum ([uite strongly arched. 

 D. I-'acial cones exceedingly short and small, scarcely projecting biyoiul 

 vertex ; labrum easily visible from in front ; antennx inserted on 

 frons and base of facial cones ; vertex distinctly raised plate-like, 

 and usually conspicuously colored; margin of vertex colored dilTer- 

 ently from discal portion. .\nal valve of male genitalia bilo- 

 bate ; claspers not acute at apex. I'aratrioca Crawford. 

 DD. Facial cones at least moderately long, or not exceedingly short: 

 labrum not visible from in front. 

 K. Thorax broader than entire width of head including eyes. F'acial 

 cones normal, usually moderately loiitj. rather acutely rounded 

 apically, more or less divergent. Trioza Forster. 



(Petalolyma Scott) 



EE. Thorax distinctly narrower than entire width of head including 



eyes. Facial cones long, very slender and acute, closely appressed 



and not divergent in the least. Ncotrioza Crawford. 



A.\. Radius shorter than basal portion of subcosta ; discoidal portion of 



subcosta almost wanting. Ccropsylla Riley. 



General Revised Synopsis of the Genus Trioza 



A. Forewings not entirely hyaline ; with more or less dark banding. 



B. Subcosta bordered with dark band ; radius straight, shorter than second 



cubital ; first furcal two-thirds as long as third ; genital segment of 



female very short; anal valve of male obtriangular. with large 



posterior lobe. 7". calif ornica Crawf. 



