254 



[April, 



ferences of the elytra alone being a sufficient reason for doing this. 

 Next, Dr. Franz Low, in his " Systematik der Psylloden," published 

 in the " Verh. z.-b. Ges.," xxviii, pp. 605—609, divided the group into 

 sub-families, and assigned to each division various genera, which are 

 justifiable by the structural characters he points out ; thus reducing 

 the whole family into small groups easy of recognition. 



The following list, prepared mostly in accordance with Dr. Low's 

 views, contains all the additions made to the British species since 

 the publication of my Monograph. His sub-families are four in 

 number, viz. : — Liviince, Aphalarince, PsyUince, and Triozince. 



PSYLLINA. 



Sub-family. 1. LIYIIN^. 

 Livia, Latr. 



juncorum, Latr. 



Sub-family. 2. APHALAKIK^. 



[EUPHYLLURA, Forst. 



no British representative.] 

 Ehinocola, Forst. 



1. ericce, Curt. 



callunce, Boh. 



2. aceris, Linn. 

 Aphalaea, Forst. 



1. picta, Zett. 



Jiavipennis, Forst. 

 sonchi, Forst. 

 innoxia, Forst. 

 alpigena, M.-D. 



2. nebulosa, Zett. 



radiata, Scott. 



graminis, Thomson (nee Linn.). 



3. exilis, Weber et Mohr. 



4. calthce, Linn. 



polygoni, Forst. 



5. artemisice, Forst. 



6. nervosa, Forst. 



Sub-family. 3. PSYLLIOE. 



Psyllopsis, F. Low (Psylla,auct.partim) , 



1. fraxinicola, Forst. 



2. fraxini, Linn. 

 [CALLOPHYA,F.L6w(Psy£ta,auct.£>ar^m) 



contains no British species.] 



Psylla, F. Low (Geoff., Latr.,&c.,^a?^im). 



1. pruni, Scop. 



fiunipennis, Forst. 



2. costatopunctata, Forst. 



ferruginea, Forst. 

 cratcegi, Schrk. (nee Scop., Forst.). 

 annulicornis, Boh. 

 triozoides, Leth. 

 quercus, Thomson (nee Linn.). 

 puncticosta, Thomson. 



3. costalis, Flor. 



nobilis, M.-D. 

 picta, Forst. ?. 



4. simulans, Forst. 



pyrl, Scott (nee Linn., Curtis).?* 



5. pyricola, Forst. 



6. pyrisuga, Forst. ?. 



pyri, Schdbg. (nee Linn.). 

 aurantiaca, Grour. 

 austriaca, Flor. 

 rutila, M.-D. 

 rufitarsis, M.-D. 



7. peregrina, Forst. 



car pint, Forst. ?. 

 cratcegicola, Flor (nee Forst.). 



8. mail, Schdbg. 



ulmi, Forst. (nee Linn.). 

 aeruginosa, Forst. 

 cratcegicola, Forst. (nee Linn.). 

 rubida, M.-D. 

 claripennis, M.-D. 

 viridissima, Scott. 



* I only discovered that the insect described by me as Ps. pyri ought to be referred to the 

 Ps. simulans, Forst., after receiving specimens of the true species from Dr F Low As far as the 

 outward appearance of the two species goes, they are extremely like each other, but the falcate 

 form of the processes in Ps. pyri at once settles the question, yet we are left in doubt whether 

 Curtis's species was not the Ps. simulans, Forst., and whether we possess the true Ps. pyri in 

 England. 



