BY n. J. TILLYARD. 



649 



the scales that lie closest to the veins are elongate and narrow; 

 and tluit, tlie further we go away from a vein, the hroader and 

 shortei- the scales become. Thus we can find, in this one insect, 

 all stages in the evolution (^f a scale from a macrotrichion present 

 upon different parts of the wing. 



Similar variations in the form of the scales, (X)nnected with 

 their positions in relation to the veins, are to he found in the 

 Micropfj'ruyidit' (Text-iig..i.S); Init, in this family, the broader 

 scales ai-e much more abundant, and may frequently be seen (juite 

 close up to the veins. 



a 



Text-tig. 33. 

 Three types of scales found in the family Micropfery<jid<P', ( x 400) : a, from 

 Eriocrania ■sttnipurpvref /a Hteph.; h, from Mnemonica Hnhpurpurella 

 Haw,; c, from Sahatliica inroii(/nfe//fi Walk. (All three types may 

 be found upon any one genus). 



In the JIf'pialidcc, both narrow, lanceolate scales and moder- 

 ately V)road, oval ones are scattered all over both membrane and 

 veins, interspersed with fairly runnerous, slender, flexible hairs, 

 or macrotrichia which have remained unaltered in form. 



It vvill not be necessary, foi- the purposes of this paper, to 

 follow out the many specialisations to be found in the scales of 



