330 



Professor E. B. Poulton on colour-relation 



Dates in 

 1893. 



Dark purplish-brown 



glossy twigs, 



probably of birch. 



9 on twigs, 4 on 

 green. Alldark brown, 

 some with a little 

 green. 



XI. 



Reddish-brown 



twigs. 



(Aug. 

 twigs, 1 



7.) 14 

 on crreen. 



i Aug. 8, 



XII. 



Bark covered with 



bright yellowish -green 



powdery lichen, the colour 



of which faded and left 



the dark bark. 



(Aug. 10.) 13 on 

 twigs, '2 on gi'een. 

 All brown, mostly 



I (Aug. 10.) 11 on 

 I twigs, 2 on green. 



I 11 purplish-brown, 2 , _, 



Aug. 1 2. ■ rather paler. Several i rather darker than 

 larvae with green twigs, but 4 rather 

 I patches on sides. ! paler. Several patched 



; with gi'eeu. 



Aug. 15. 



Aug. 19. 



Aug. 21. 



Aug. 26. 



Aug. 30. 



\ 12 on twigs, 1 on 

 green. As before. 



12 on twigs, 3 on 

 green. As before. 



10 on bark, 3 on 

 green. 10 of a rich 

 dark brown patched 

 with lighter brown 

 and green : 3 lighter 

 brown variegated with 

 still paler brown and 

 green. All but one of 

 these paler larvte with 

 little white dashes on 

 sides. The green marks 

 less pronounced than 

 in XIII and XIV. 



10 on bark, 2 on 

 green, 1 on muslin. 



(Aug. 14.) 10 on 

 bark, 2 on green. All 

 but 2 very dark brown, 

 with far less green 

 than XIII and XIV. ; 



10 on twigs, 2 on 10 on twigs, 5 on 

 green. Purplish- green. All brown, 

 brown, several with a several patched with 

 little green. 2 rather green, 

 paler brown. | 



12 larvaj, as before. 



8 on twigs, 4 on j (Aug. 22.) 12 on 

 green. 10 purplish- \ twigs, 3 on green, 

 brown, 2 brown. Only | All brown, 8 resemb- 

 1 or 2 slightly marked , ling twigs, 2 rather 

 with green. j darker, 2 rather 



i lighter. 



(Aug. 25.) 12 on 

 sticks. 



9 on sticks, 2 on 

 green. 1 mature. 



Sept. 5. 



Mostly mature. 2 

 feeding Sept. 8. All 

 mature Sept. 13. 



Re-fed. 



2 mature, and 2 

 move on Aug. 31. 



(Sept. 4.) Nearly 

 all mature. Only 1 

 feeding Sept. 9. 



(Aug. 22.) 9 on 

 bark, 3 on green. 



10 on bark, 2 dead. 



6 on bark, 4 on 

 green. The colour of 

 the lichen had faded, 

 and left the dark 

 bark. 



(Sept. 4.) Larvie 

 becoming mature. A 

 few still feeding Sept. 

 9 and 13. 



