British Homoptera-Cicadina. 93 



each side of the pale dorsal line black, on the dark side portions a 

 few rows of pale spots. Elytra less than half as long as abdomen. 

 Legs entirely pale. In some examples the dark markings, in- 

 cluding the short line at the apex of the clavus, are entirely 

 wanting. Length, 2| — 3^ mm. 



Macroptcrous for77i. — Sentellum nearly three times as long as 

 the pronotum, its keels obsolete. Elytra about twice as long as 

 abdomen, whitish hyaline, inner margin at the apex of the clavus 

 with a short black Une ; nerves pale brown, darker behind, closely 

 set with fine setigerous granules. Length, 4 — 4^ mm. 



Very common. 



V. Stiroma, Fieb. (PL I., fig. 21). 

 Fieb., Grundz. Delph., 521, 18 (1866). 

 Frons smooth with two keels on the disc, which, although some- 

 times obsolete above, are always observable near the clypeus. 



Table op Species. 



1 (4). Facial keels filiform throughout. 



2 (3). Facial keels strong, separate at the clypeus, 



mouth of pygofcr (male) triangular . . 1. alhomarglnata, 



3 (2). Facial keels feeble, conlluent at the clypeus, 



mouth of pygofer (male) wide-oval, widest 



above the middle . . . . . . . . 2. boreaUs. 



4 (1). Facial keels obsolete above. 



5 (10). Pronotum and scutellum not striped with 



black. 



6 (7). Frons narrow-oblong, entirely yellow .. S. jiteriiJi'^. 



7 (6). Frons wide, narrowed and marked with 



black just above the clyi^eus. 



8 (9). Styles obliiiuoly truncate at the apex, each 



angle produced into a small pointed tooth 4. affmis. 



9 (8). Styles acuminate at the apes . . . . 5. hicarinata. 

 10 (5). Pronotum and scutellum yeUow, each with 



two black stripes . . ... . . . . 6. nigrolineata. 



1. Stiroma albomarginata, Curt. 



Delphax albomargimita, Curt., Ent. Mag., i., 195 ; 



Marsh., Ent. Mo. Mag., i., 227, 8. 

 D. mcesta, Bob., Sv. Ak. Handl., 59, 24 (1849) ; Stal, 



Ofv., 8, 82 (1854). 

 D. collaris, Stal, Ofv., 175, 3 (1853). 

 D. addplut, Elor, Ebyn. Liv., ii., 81, 26. 

 Bitropis adelpha, Eieb., Grundz. Delpb., t. 8, fig. 18 



( (? genitaba) ; Kirscbb., Cicad., 43, 5. 



