104 BULLETIN 85, UNITED STATES NATIONAL MUSEUM. 



HEMITRIOZA, new genus. 



Head much narrower than thorax, deflexed; vertex not raised 

 platelike; genal cones not long, divergent; clypeus small. Eyes 

 very small. Antennae not more than twice as long as width of head. 

 Thorax arched quite strongly; pronotum short, depressed below 

 level of head and prsescutum, descending strongly cephalad; pro- 

 pleurites as in Trioza. Hind tibiae with three apical spines within 

 and one outside; basal tarsus of hind legs without apical clawlike 

 spines. Wings short, membranous; media and cubitus often with a 

 long or short petiole or without one (varying on wings of individual) ; 

 basal vein long. Male often much smaller than female. 



Type of genus. — Hemitrioza sonchi, new species. 



This genus is distinctly triozine in general form, but in wing vena- 

 tion it approaches Psylla. Its position seems to be more or less 

 intermediate between Psylla and Trioza, hence the name. 



HEMITRIOZA SONCm, new species. 



Fig. 402. 



Trioza sonchi Riley (nomen nvdum), Proc. Amer. Ass. Adv. Sci., 32:319.— -A ttlmann 

 13:55. 



Length of body, 1.7 mm; length of forewing, male, 2; female, 2.5. 

 General color, red to orange; antennae white, black at tip; beak 

 black; fore and middle tibiae and all tarsi whitish; wings with a 

 broad reddish band across the middle and three spots on hind mar- 

 gin. Head and thorax coarsely punctate. Male much smaller 

 than female. 



Head rather small relatively; vertex more than half as long as 

 broad, mth a large foveal depression on each side of median line, 

 emarginate in front over ocellus; genal cones not quite as long as 

 vertex, broad at base, subacute, widely divergent, subvertical, pubes- 

 cent. Eyes very small. Antenna about twice as long as width 

 of head, III thicker than succeeding segments. 



Thorax rather strongly arched, broad; pronotum short; scutum 

 large. Wings hyaline, relatively short, about twice as long as broad, 

 conspicuously colored as described above; petiole of media and 

 cubitus variable in length even on wings of an individual; radial 

 sector very short ; marginal cells subequal. Hind wings very small. 



Genitalia. — Male. — Forceps about half as long as anal valve, thick 

 at base and converging to apex to a sharp toothlike point, arcuate 

 somewhat; anal valve rather large, elHptical (from side view), 

 broadest at middle; forceps and anal valve quite densely pubescent. — 

 Female. — Genital segment short, a little longer than preceding seg- 

 ment;, dorsal valve longer than ventral, 



