THE ENTOMOLOGIST. 33 



circles of life are combined; and some part of the substance 

 of the oak-leaf is transformed into oak-spangles by means of 

 a gall-fly. In the oak-currant the circle is more complicated, 

 for not only gall-flies, but also parasitic flies take part in the 

 work. In the oak-apple the arrangement is far more intricate, 

 for very numerous kinds, perhaps one hundred in number, 

 representing all the chief orders of insects, are occupied in 

 it; and it is not only inhabited by insects, but is also 

 frequented by Acari or mites, whose chief dwelling-place is 

 wood-moss, where the species of Bryobia, Zeles, Tydeus, 

 Iphis, Murcia, Nolhrus, Oribatcs, Pelops, Penthaleus, Hoplo- 

 phora, Eumffius, Erymaeus, Caligonus, Carabodes, Celaeno, 

 Cepheus, and the more elegant Eupodes and Linopodes 

 abound ; and British Entomology is in need of a book on 

 these wood-moss mites; and oak-apples aff'ord abundant 

 materials for another volume. Andricus terminalis, by means 

 of its punctures and egg-laying, is the means of forming the 

 oak-apple, which supplies its offspring with board and 

 lodging; but numerous enemies appropriate to themselves 

 the bodies, or the food and habitation, of this offspring ; and 

 other kinds avenge the Aborigines by consuming their 

 invaders. Some kinds inhabit the oak-apple for two months ; 

 one species lives a year in it; and -the successive generations 

 of this fly pass from oak-apple to oak-apple. But the life- 

 history of the other kinds requires to be traced for ten months 

 elsewhere. Each oak-apple is tenanted by many individuals 

 of the Teras, and there is much to be observed as to how the 

 grubs are distributed through the oak-apple during its 

 growth, and in noticing the successive arrival of other 

 species, which find their way into the oak-apple, or insert 

 their eggs therein. In conclusion I will mention two or three 

 oak-apple insects, in addition to those which I have previously 

 noticed. Lampronota Segmentator: — this is probably a 

 parasite of Pcecilochroma corticana (Fam. Tortricida?), a 



moth that frequently emerges fiom oak-apples. Psylla : 



— I have not yet ascertained llic name of .this species; it has 

 a very close resemblance to P. Buxi. Anthomyia ))luvialis : — 

 another species of this genus, A. canicularis, has been reared 

 from the cottony oak-gall, the habitation of Andricus Ramuli. 

 Eulophus Gallarum is frequent in these two galls. — Frauds 

 Walker:' (Entom. v. 431.) 



F 



