224 [March, 



4<-cincfus is so great, that it is possible I may be wrong. A. succincttts, 

 Lep., is usually quoted as a syuonym of zona, but the description does 

 not quite agree with that species. It has, for instance, the 4th and 

 5th segments yellow, the 7th black, and the scutellum yellow. Stephens' 

 description is merely a copy of St. Fargeau's succinctus (Mon. Tenth., 

 93, 2(56), so, in the absence of specimens, it throws no light on the 

 matter. Succinctus probably = Schcefferi. 



A. vidmts is only known as British by a solitary specimen re- 

 corded by Newman (Ent., 18G9, p. 217). It was identified by Mr. 

 Smith, and is said to have been taken many years before the date it 

 was recorded in the " Entomologist," in Darenth. Wood. It is a com- 

 mon species all along the Mediterranean to Greece. It is certainly a 

 southern insect, and one I scarcely expected to occur in Britain. It 

 is easily known by its deep violet-black body and wings, and white 

 band on the abdomen, but this, however, may be absent. 



(To he contimiedj . 



TEANSITOEY OE PEOVISIONAL INSECT-FOEMS. 

 BY J. LICHTE^"STEIN. 



Although generally, and in France more particularly, received 

 with great incredulity, my theory of the biology of plant-lice, and 

 PempMgincB specially, begins to be accepted by reason of its truth. 



The cycle of life shows two winged forms very different from 

 each other, the emigrant {Pseudogyne migrans) giving birth to an 

 agamous ])roles, and the pupiferous {Pseudogyne pupifera) producing 

 sexuated individuals. Generally the wiuged emigrant form only has 

 been noticed by authors. Being very easy to find in the large galls 

 which some of them form on our commonest trees, such as poplar and 

 elm, in the north, and TerehintJi us in the south, they long ago attracted 

 the attention of observers ; yet although from the earliest to the latest 

 authors — Theophrastus, B.C. 371, to G. Passerini, 18G0, winged gall 

 plant-lice were noticed, they were only the emigrant form. I was, I 

 believe, the first to trace in Phylloxera quercus, the full biological cycle, 

 including the migration from one plant to another (a fact already 

 noticed by F. "Walker, but without discrimination of the difference 

 between the two winged forms). Targioni's observations on PhyUoxera 

 jlorentina migrating from Quercus Ilex to Quercus sessilijlora con- 

 firmed my theory, and he acknowledged at once that his PhyJl. 8i(jnoreti 

 was only the second winged form oiforentina. 



