158 THE MOTHS OF THE BRITISH ISLES. 



but they are paler in colour and more glossy ; hind wings 

 whitish and glossy. In the female, the wings are useless 

 for flying, but still they are larger than those of h'umata. 

 The front pair have a blackish band. (Plate 58, Figs. 6 and 

 7 J, 5 ? ; ova. Plate 59, Fig. i.) 



The caterpillar is greenish, with a greyish stripe along the 

 back, another edged above with yellow along the black spiracles, 

 and a greyish line between the stripes ; the head is black. It 

 feeds, in May and June, on birch, and the moth does not appear 

 until October or November. 



At one time considered to be a purely northern species : the 

 earhest known British specimens, four in number, having been 

 captured at Petty Pool, Delamere, Cheshire, on October 31, 

 1848. It is now known, however, to have a wide distribution 

 in the south of England. Northwards, its range extends 

 throughout England and Scotland up to Moray. It is found 

 in South Wales ; also in Galway, Monaghan, and Connemara, 

 in Ireland. 



The Tissue {Triphosa diibitata). 



The fore wings of this glossy species (Plate 60, Figs, i, 2) 

 are pale brown, tinged more or less strongly with rosy or 

 purplish ; there are numerous darker and paler cross lines, the 

 most distinct and constant being the blackish basal, and the 

 two forming the edges of the central band ; the latter are 

 marked with black ; the submarginal line is whitish, wavy, and 

 sometimes broken up into dots. The species varies consider- 

 ably in tint, some specimens inclining to pale greyish brown, 

 others to smoky brown. Hind wings, whitish grey, with several 

 darker grey cross lines ; in dark specimens these wings are 

 smoky grey. Ab. cinereata^ Stephens, is a small pale greyish 

 form, almost without rosy tinge and with fewer cross lines. 



The caterpillar (Plate 62, Fig. i) is yellowish green with 



