British species of Psyllidce. 545 



Thorax: pro- and meso-notum green or yellow, without 

 paler longitudinal lines. Elytra clear, transparent; apex 

 almost imperceptibly fuscous; nerves from the base to the 

 apex of the petiole yellow, from thence to the apex brownish- 

 yellow ; petiole of the cubitus and the lower arm subequal or 

 nearly 'so. Costal stigma sometimes greenish, long, wide 

 at the base, diminishing gradually to the apex. Legs 

 yellow. Claws frequently brown. 



Abdomen entirely green or yellow. 



Length 1^ line. 



A good character for the identification of this from other 

 o-reen species, as pointed out by Forster, is the shortness 

 Sf the loAver arm of the cubitus, which is only a little longer 

 than the petiole. I have met with this species in the Isle 

 of Wight in July, and in this neighbourhood, on ash trees 

 {Framnus excelsior), in August and September, but not 

 commonly. M. Lethierry says he finds it on elm. Dr. 

 Power has taken it at Balmuto (Fifeshire). 



Species 16. Psyllafraxini. 

 Chermes Fraxini, Lin. F. S. 264, 1013; S. N. ii. 739, 



15 ; Fab. E. S. iv. 223, 15 ; S. R. 305, 15 ; Scop. 



Ent. Carn. 140,415; Fsylla Fraxini, Curt, B. E. 



xii. 565 and pi. ; Forst. Verb. Ver. Rheinl. v. 80, 31 ; 



Flor, Rhyn. Livl. ii. 481, 16; Leth. Hem. Nord, ed. 



ii. 89, 5. 

 Yellow, or sometimes slightly orange. Head and 

 mesonotum with black patches and streaks. Face : lobes 

 much shorter than the crown down the centre, in outline 

 somewhat pyramidal. Antemicn yellow, 4 — 6 joints black 

 at the apex, 7 — 10 black. Elytra clear, transparent; 

 nerves and costal stigma yellow,* except when intercepted 

 by the fuscous black-markings. 



Head : crown generally black, side margins yellow or 

 orange, posterior margin lightly concave. Face: lobes 

 frequently black, much shorter than the_ crown down the 

 middle; in outline somcAvhat pyramidal. Antenna: 

 yellow, reaching to beyond the base of the stigma, 4-6 

 loints black at the apex, 7—10 black, 4th about half as 

 long as the third. 



Thorax: pronotum pale yellow; mesonotum yellow 

 or orange ; anterior portion with two black triangular 

 patches in front, and a somewhat square spot on the sides 

 posteriorly, in the channel; posterior portion with four 

 longitudinal, broad, black streaks, not unfrequently joined 



