TRIFID.^. 355 



bands ; yet even in this district well-marked individuals 

 sometimes occur, and farther north, in Cumberland, and in 

 both the east and west of Scotland, the normal brilliant colour- 

 ing of the bands is resumed or even exceeded. Specimens 

 also occur in which the ground colour has a more yellow tint, 

 even almost to pale yellow. In Mr. Sydney Webb's collection 

 is a beautiful example of this shade, but with the transverse 

 bands ^^^Xq 'pui'ijlc. 



On the wing in September and October, but in Scotland, 

 where the autumn advances more rapidly, it is sometimes 

 taken in abundance at the end of August. 



Larva rather stout, slightly tapering at each end ; head 

 rounded and shining, pale brown reticulated with reddish- 

 brown ; general colour hazel-brown, cinnamon, or pale 

 chocolate-brown, often with a dull crimson tinge, and 

 obscurely dusted with darker ; there are traces of a whitish 

 threadlike dorsal line shaded on each side with grey on the 

 anterior segments ; usual raised dots whitish or pale grey 

 encircled with dark grey or brown, but often invisible; 

 spiracular stripe broad, very conspicuous, pure white ; 

 spiracles black, distinct ; undersurface paler than the ground 

 colour ; the usual dots below the spiracular line are more 

 distinct than those upon the back and sides. (C. Fenn.) 



Mr. Buckler says that the very young larva is grey-drab 

 or pinkish-grey, with deeper grey dorsal vessel visible to the 

 tenth segment, head glossy light brown ; after a week 

 shining green, with whitish dorsal, subdorsal, and lateral 

 lines, and a broad whitish spiracular stripe ; also that these 

 lines gradually become clear white, and after another moult 

 the ground colour more bluish -green, with the spiracular 

 stripes edged with black ; from this the subdorsal and lateral 

 lines gradually fade out ; at a mouth old the green colour 

 begins to be exchanged for brown and the adult colour is 

 gradually assumed. 



April to the beginning of June on oak, elm, birch, sallow, 



