Light reflected from 

 backgrounds. 



Elfecta produced. 



Larvfe. 



Pupae. 



Amphidasis 

 bctularia. 



Vanessa 

 Other sensi- urtictc, 

 tive larvse. 1886 and 

 later. 



Pieris bras- 

 sicie and P. 

 raprr, 1886 

 and 1888. 



Other 

 pupa. 



Black paper. Very faint 

 continuous spectrum. It 

 is probably this faint reflec- 

 tion, not stronger in one 

 part of spectrum than an- 

 otlier, whicli acts as the 

 stimulus and accounts for 

 the difference, which is 

 usually very great, between 

 darkness and black surfaces 

 in strong light, the latter 

 causing the more powerful 

 effects. A dead or var- 

 nished surface produces the 

 same results. The dark 

 twigs also made use of may 

 be safely included here. 



Light brown ti-<t:ue-paiier 

 on a background of white 

 paper (LXIII.). Strong 

 general absorption, least in 

 red, becoming almost com- 

 plete in blue. 



Brown twUjs. Very similar 

 to the above, except that 

 no blue is reflected. 



Deep red paper. Only one 

 shade used. Spectrum re- 

 duced to red, which is 

 but slightly dimmed. Com- 

 pared with orange (below), 

 it differs in the absorption 

 of parts about solar line D, 

 and above it. 



Deep oraniie priper. The 

 only orange paper used. 

 Absorption begins a little 

 above line D, removing 

 nearly all green and every- 

 thing else. All below D 

 reflected. 



Orange enamel (painted 

 on twigs). Red, orange, and 

 yelbiW reflected, the rest 

 absorbed. Very similar to 

 spectrum of orange paper, 

 but a little shorter. 



Dark 

 larvffi : 



blackness 

 varying 



with that 

 of back- 

 ground. 



Brown 

 larvffi. 



Green 

 larvas. 



Green 

 larv£e. 



Dark 

 larvse. 



Dark 

 pupffi. 



Dark 

 pupa3. 



Dark 

 pupffi. 



Dark 

 pupa3. 



Green 

 pupic. 



Dark 

 pupa3. 



Dark 

 pupa3. 



Dark 

 pupas. 



Dark 

 pupfc. 



Green 

 pupa'. 



