LAWSON: KANSAS CICADELLID^. 



67 



Idiocerus verticis (^ay) . 



(PI. 4, figs. 4-6.) 



Jansus rerticis Say, Jl. Acad. Nat. Sci. Phila., A"I, p. 308, 1331; Compl. Writ., ii, 

 I). 383. 



B!/thof!Coims r-erticis Uhl., Bui. U S. Geol. Geog. Surv., iii, p. 465, 1877. 



Idiocerus vertiris Van D., Psyche, v, p. 389, 1890 



Idiocerus verticis G. & B., Hemip. Colo., p. 80, 1895. 



Idiocerns verticis O. & B., Proe. Dav. Acad. Sci., vii, p. 132, 1898 . 



Idiocerus verticis Osb., 20th Rept. N. Y. St. Ent., p. 507, 1905. 



Idiocerus rerticis DeL., Teun. St. Bd. Ent., Bui. 17, p. 11, 1916. 



Idiocerus verticis Van D., Cat. Hemip. N. A., p. 577, 1917. 



Foi-^n: The smallest member of the genus in Kansas. Length, 4.25 to 

 4.5 mm. 



Color: Pale brownish to nearly white. Pair of small, black spots on 

 vertex. Pronotum with light-brown markings on disc. Scutellum with 

 basal angles black or brown. Brown nervures of elytra usually inter- 

 rupted with white, dark specimens showing light spot across middle of 

 clavus. 



Exteiiial genitalia: Female, last ventral segment much as in alter- 

 natiis, short,, posterior margin usually slightly sinuate on either side of 

 the slightly produced and faintly notched median portion, lateral margins 

 strongly narrowed posteriorly; pygofers exceeded by the ovipositor by 

 about one-third their length. Male, last ventral segment as in alternatus, 

 with long lateral lobes, large median incision with small median lobe, 

 median incision sometimes not as deep as in alternaUis; plates, long and 

 slender, equalling the long pygofers; antennas very short and with very 

 large discs. 



Male inteiiial genitalia: Styles smaller than in snowi, basal part more 

 slender; connective with three basal processes, as in snoivi, but upper 

 portion narrow, only half as wide; cedagus Y-shaped, with distinct base 

 and slender upper arm, lower arm simple, without the arrowhead ap- 

 pearance as in snowi; collar around base of anal tube slender and open 

 slightly at tip, forming almost a complete circle. 



Distrihution: A species seemingly occurring over the state, 

 as shown by the following map : 



Hosts: Willows. 



