854 Mr. VouUon' a further experiments upon 



¥. White Surroundings. 



Experiments XXVIII. — XXX. 



XXVIII. 



Cyliuder. 

 Height . . 149 mm. 

 Intern, diam. 71 mm. 

 Ai)prox. cap. COO cc. 



Many white paper spills 

 iutermixecl with and sur- 

 rounding food-plant. 



July 11. — 10 young 

 larva3 introduced from 

 "first stock, "having been 

 previously on green leaves 

 and twigs alone, which 

 had become somewhat 

 brown bv July 11. 



July 21.— Larvffi 22-0 

 mm. long : 

 3 bright green, 

 6 greenish, 

 1 light brown. 

 Some of the larvai had a 

 very whitish appearance ; 

 this was noticed some 

 days previously. 



July 23. — More spills 

 added. 



July 30. — All in last 

 stage ; all resting on the 

 spills : 



8 very whitish & opaque- 

 looking, 



1 green, 



1 brouniish {small inlast 

 stage). 



Any. 3. — Carefully com- 

 pared ; all 10 nearly ma- 

 ture, and extremely white 

 and opaque. The results 

 were very uniform, al- 

 though 2 were faintly 

 grc^enish and 1 faintly 

 brownish, but these tints 

 were nearly hidden in the 

 predominant tendency 

 towards white. One of 

 each was selected for 

 painting. 



XXIX. 



LamiJ-shade. 

 Height . . 16.5 mm. 

 Appro.v. cap. 1300 cc. 



Many rough twigs, 

 chiefly of Qnercns cerris 

 and elm, were enamelled 

 twice with white, and 

 intermixed. 



July 14. — 10 young 

 larvEB introduced, as in 

 XXVIII. 



XXX. 



Lamp-shade. 

 Height . . 147 mm. 

 Appro.r. cap. 550 cc. 



Similar to XXIX., ex- 

 cept that twigs were only 

 enamelled once, A hence 

 were not so brilliantly 

 white. 



July 25.— 

 5 green, 



1 greenish, 



4 brown (not dark). 

 Any. 7. — All last stage: 



4 bright green (dorsal 

 line very distinct on 1, 

 faint on 2, overspread 

 with grey on 1), 



4 wliitisli, 



2 very liyht grey, in- 

 clining to whitish. 



The whitish larvte were 

 duller and more inclining 

 to other colours (green- 

 ish, brownish or yellow- 

 ish) than those of XXVIII. 

 They were, however, quite 

 distinct opaque whitish 

 forms. 



July 16. — 9 introduced 

 from the "second stock," 

 having been on green sur- 

 roundings, in darkness by 

 day, and lamp-light at 

 night. 



July 25. — 9 alive : 

 7 green, 

 2 greenish. 



Aug. 7. — All in last 

 stage : 



4 bright green (3 with 

 distinct dorsal line, 1 

 tending to be over- 

 spread with grey), 



4 whitiuli (duller than 

 XXIX.), 



1 light brown, like the 

 10 larvffi in VI. 



