328 FOREST ENTOMOLOGY. 



Synopsis of Arboreal Species.^ 



A. Pi/f/idmm withfou); vareUj loitlifive, groups of eircumgenifal glands. 



(1) Short serial group of lateral dorsal pores absent. Puparium 



reddish-pink in the young, snioky-grey in the old examples. 

 On oak ....... Zonatus. 



B. Piigidium always with five groups of circuingenital glands. 



(2) Serial group of dorsal pores present. Puparium flat, convex 



grey with a darker central zone. Hitherto found on fruit- 

 trees ...... Ostreaeformis. 



C. Piigidium ivitli club-shaped glands. 



(3) Groups of tubular spinnerets connected, Avith pores on both 



surfaces of pygidiura ; circumgenital glands almost continuous. 

 Puparium bright-fulvous. On liolly . . Britannicus. 



AspiDiOTUs ZONATUS (Fraueufeld). 



This insect is found on oak, but, so far, it has been rarely recorded. 

 One of the first discoveries was by myself at Agden, in Cheshire, Sept. 

 1892. It has been found fairly often in Cheshire, but never occurs 

 in any great numbers. 



As regards life-history, the egg-laying takes place early in J\Iay, and 

 the larvae hatch soon afterwards. As soon as the first larval moult 

 takes place, the sexes not only assert themselves, but they separate, 

 . the males moving on to the leaves, and fixing themselves to the 

 midrib and veins, and the females congregating on the stem. But 

 tliough separated, it is, after all, only in the metamorphic stages, 

 inasmuch as it is only for the requirement of pupal development on 

 the part of the male. As the males emerge from the puparia on the 

 leaves with fully developed wings, it is obvious they have no distance, 

 or diiUculty, to move from tlie leaf to tlie stem for nuptial rites and 

 associations. 



AspiDiOTUs BRITANNICUS (Xewstead). 



Tliis is a species which, so far, has only l)een found on holly and a 

 species of fern cultivated under glass in the immediate neighbourhood 

 of London. The scales are circular, of a dusky-brown colour, and on 

 the slightest disturbance fall readily from the leaf. The males can 

 be distinguished from the females by the smaller size of the scale. 



' Modified from Xewstead's Monograph, vol. i. 



