No, 34-] HEMIPTERA OF CONNECTICUT: CICADELLIDAE. 147 



Tribe TYPHLOCYBINI. 

 Eupteryginae. 



The chief characters which -separate this group are used in the 

 preceding key. The frequent absence of the ocelli and the un- 

 branched condition of the sectors which extends to the apical cells 

 before dividing or giving off cross nervures, so that no anteapical 

 cells are formed, are characteristic of the following species. 



Although this group is composed of the smallest and most fragile 

 of the entire family, it contains some of greatest economic impor- 

 tance which are known for their damage from coast to coast. 



Key to Genera. 



1. Posterior wings with sectors ending in a marginal vein. (Fig. 14, 



ib, 3b, 4a.) 2 



Posterior wings without marginal vein, sectors extending to wing 



margin. (Fig. 14, 5c, 6b, 7b.) 4 



2. Elytra with well-defined appendix. (Fig. 14, ic.) Alebra, p. 147 



Elytra without appendix. (Fig. 14, 3c, 4b.) 3 



3. Posterior wing with two apical cells. (Fig. 14, 3b.) Dikraneura, p. 148 

 Posterior wing with one apical cell. (Fig. 14, 4a.) Empoasca, p. 151 



4. First two sectors of posterior wing uniting so that only three veins 



extend to wing margin. (Fig. 14, 6b, 7b.) 5 



Posterior wing with all four sectors ending in the wing margins. 

 (Fig. 14, 5c.) Typhlocyba, p. 155 



5. Elytra with outer sector not uniting in any part with middle sector ; 



a common cross vein between them forming base of oblong apical 



cell. (Fig. 14, 6a.) Erythroneura, p. 159 



Elytra with outer and middle sectors uniting for a short distance, 

 posterior to cross veins, thus forming a triangular apical cell. 

 (Fig. 14, 7a.) Empoa, p. 157 



Alebra Fieber. 



Characterized by the blunt feebly curved, parallel-margined 

 head, which is narrower than pronotum, the elytra with a distinct 

 appendix and the wing with a marginal vein. 



Key to Species. 



1. Entirely orange-yellow or white with yellowish elytral suture, 



without dark markings .albostriella 



Dark in color or pale with dark markings 2 



2. White to yellow, a brownish area on tip of clavus and scutellum 



and disc of pronotum brownish albostriella var. wahlbergi 



Deep smoky to black, especially clavus and tips of elytra dark, face 

 yellowish fumidus 



A. albostriella (Fallen). Cicada albostriella Fallen. Cicada 

 elegantula Zetterstedt. Typhlocyba pallidula Walsh. (Fig. 

 14, ia, b, c.) 

 Hemip. Suec, Cicad., 54, 1826. 



Head blunt, rounded and parallel-margined, white or pale yellow, 

 often with a yellow stripe along suture. Tarsi black and tips of 

 elytra smoky. Length 4 mm. 



