5-14 INIr. Jolin Scott's Mono(jr<ip}i. of the 



longer than the crown down tlic centre; base broadish; 

 apex somewhat acute; outer margin concave; divergence 

 at the aj)ex about equal to the base of either. Ahtenncp 

 somewhat brownish; 1 — 2 joints green, or the latter yellow, 

 9—10 black. 



Thorax: pro- and mcsto-notiim green; after death more 

 or less yellow. Ehjtra clear, transparent, at least 2^ times 

 as long as broad; greatest breadth beyond the middle; nerves 

 fine, white or slightly clouded towards the a])ex; costal 

 stigma pale green, ehanging to whitish after death, Avide 

 at the base, and gradually ta])ering to the apex, Avhich is 

 a little beyond, in a line Avith the apex of the npper arm of 

 the cubitus; radius concave in the middle, at which point 

 it is slightly nearest to the stigma. Legs green. Claws 

 brownish. 



Abdomen bright green. 



Length H line. 



This species belongs to the same group as P. mail and 

 P. fraxinicola. It is larger than the first of these species, 

 and about the size of the latter, and may at once be dis- 

 tinguished fi-om either by its bright green colour. A few 

 s})ecimens have been taken by jNlr. Douglas on the common 

 buckthorn {Rlianmns cafharticus) or apple (he is not 

 certain which), at Lee, in September ; probably a form of 

 P. niali. 



Species 15. Psylla fraxinicola. 



Psylla fraxinicola, Forst. Verh. Ver. Kheinl. v. 76, 20; 

 Leth. Hem. Nord, ed. ii. 89, 5; Psylla unicolor, 

 Flor, Rhyn. Livl. ii. 479, 15. 



Gi'een or yellowish. Pace : lobes shorter than the crown 

 down the centre, exterior margin sloping rapidly to the 

 stumpy apex. AntenncB yellow, 3 — 8 joints at the apex 

 narrowly dark brown, 9 — 10 dark brown. Elytra clear, 

 transparent ; apex almost imi)erceptibly fuscous ; nerves 

 brownish-yellow towards the apex; petiole of the cubitus 

 and the lower arm subequal or neai'ly so; costal stigma 

 long, wide at the base, diminishing gradually to the apex. 



Head green or yellow. Croivn : posterior margin almost 

 straight. Pace: lobes shorter than the crown doA\n the 

 centre, exterior margin sloping rapidly to the stumpy apex. 

 Antenna: yellow, 3 — 8 joints at the apex narrowly dark 

 brown, 9 — 10 dark bi'own or black, sometimes from the 

 4th to the a]iex dusky; 4tli and 5th together a little longer 

 than the 3rd. 



