242 [October, 



opinion, aberrant individuals : thc}^ may perhaps be referable to 

 mespilella, spinicolella, 7i., and faginella, Z., respectively. In the 

 Stainton British collection the series of " fomifoliella " includes re- 

 presentatives of hlancardeUa, oxi/accmthce, Frey, and other species, 

 while that in the continental collection contains four specimens, two 

 of which, bred from Pyrus malm, were received from Professor 

 Fritzsche as " j)omifolielJn " and are concomitelln, while the other two 

 are labelled by Stainton " Original to Zeller's descr., Zeller 11/50." 

 One of these bears Zeller's MS., label "v. Ti," and appears to be 

 concomitella, but the identity of the other seems extremely doubtful. 



The nine species here dealt with are, for the most part, very 

 puzzling and difficult to differentiate at first, and it is only by the 

 careful study of long bred series of each than one can hope to grasp 

 the subtle distinctions between them. The general pattern of the 

 markings is alike in all, and consists of a white streak from the middle 

 of the base, and four costal and three dorsal white teeth of various 

 shapes and sizes. Individuals of the same species often vary greatly 

 in size and colour, and to some extent in the exact form of the 

 markings, and aberrations occur, though but rarely, in which two of 

 the costal, or of the dorsal, teeth unite to form one, or in which one 

 of the teeth is divided into two, or is altogether absent. The presence 

 or absence of dark spots on the posterior tarsi is, in some species 

 {e. g.sorhi, Frey), a sufficiently constant character to be of great value 

 in helping one to recognise them, though in a few it is quite unstable, 

 and occasional exceptions to any rule must be expected in all. 

 Identifications can therefore only be satisfactory when based upon 

 the combination of special characters found in the individual. The 

 summer broods are, in general, smaller and paler than the spring 

 ones, and continental specimens are generally lighter and brighter 

 than British ones, ^j cowiparative notes on all the species, excepting 

 of course cydoniella, which is not known to occur in Britain, have 

 been made from series bred from the most southern counties of England 

 only, because northern specimens average so decidedly darker than 

 southern ones that a comparison in colour between the northern form 

 of one and the southern form of another would be very misleading. 

 For example, sorbi is, in the south of England, a clean-looking and 

 bright species, whereas the specimens of it that I have examined from 

 Dumbartonshire, N.B., are fully as dark as my darkest examples of 

 pyrivorella. Several of the species are by no means confined to only 

 one, or even two food-plants, which has largely helped to increase the 



