16 NORTH AMERICAN THYSANOPTERA. 



a. Fore tibiae armed at end with tooth. Females dark brown; wingB brown, with 

 whitened area near base; antennae concolorous with head, except 

 segment 3, which is light yellow. 



(45) Euthrips ulicis californicus Moulton. 

 a^. Fore tibiae not armed with tooth. 



b. Postocular spines wanting; row of spines along anterior margin of pro thorax 

 either wanting or at least not conspicuous, except often the third 

 from the outer margin. 

 c. Antennae uniformly brown to dark brown, concolorous with body; wings 

 light brown, veins prominent; spines brown, twenty-three on fore 

 vein, sixteen on hind vein, short and comparatively stout; white 

 longitudinal area near base of wing. .(46) Euthrips minutus Moulton. 

 &. Antennae with segment 3 yellowish, 4 and 5 light gray-brown, yellowish at 

 base; wings gray -brown, veins not prominent, spines on wings nor- 

 mally long and stout, fourteen on fore vein, ten on hind vein. 



(Wings may be reduced to pads) (47) Euthrips fuscus Hinds. 



y. Postocular spines conspicuous, 

 c. General color uniformly brown to dark brown, no shading of orange; antennae 

 with segments 3, 4, and 5 light brown to yellow and shaded. 

 d. Uniformly dark brown; fore wings shaded dark brown, with a large 

 whitened area extending across wing near base; spines on wings all 



dark brown (48) Euthrips insularis Franklin. 



d''. Color yellowish brown; fore wings uniformly shaded with gray. 



(49) Euthrips nervosus Uzel. 

 (/. General color whitish to yellow or yellowish to brown, no shading or orange. 

 d. Second segment of antennae with a double spine-bearing tubercle; vertex 

 of head depressed; anterior ocellus directed forward, 

 e. Color uniformly yellow; surface of body without reticulation. 



(50) Euthrips cephalicus Crawford. 

 e^. Color uniformly brown; surface of body reticulated. 



(51) Euthrips cephalicus reticulatus Crawford. 

 d'. Second segment of antennae without double spine-bearing tubercle; ver- 

 tex of head not depressed; anterior ocellus directed upward; 

 color yellowish, shaded with dusky brown. 



(52) Euthrips helianthi new species. 

 (/\ General color light yellow to yellowish brown; thorax or other parts 



decidedly tinted with orange. 

 d. Head pale lemon-yellow to light yellowish brown; thorax orange-yellow; 

 abdomen brownish yellow to brown; segment 1 of antenna whitish 

 to light brown; segment 2 dark brown. 



(53) Euthrips occidentalis Pergande. 

 d\ General color brownish yellow, not uniform; thorax orange-yellow; seg- 

 ment 1 of antenna pale yellow, 2 light brown, base sometimes yel- 

 lowish (54) Euthrips tritid Fitch. 



c?^''. General color brown to dark brown; thorax orange-brown. 



(55) Euthrips tritid californicus, new variety. 



(19) Genus Anaphothrips Uzel. 



1. Without spines on posterior angles of prothorax; cheeks straight; surface of abdo- 



men not faintly cross-striated; crescents of ocelli bright orange- 

 yellow (56) Anaphothrips striatus Osborn. 



2. With one stout spine on posterior angle of prothorax; cheeks arched; surface of 



abdomen distinctly crosa-striated', crescents of ocelli light brown. 



