tera, 
Odontopera bidentata was also sensitive to the same sur- 
roundings, lichen in the environment producing the well- 
known green patches on the dorsal surface. 
The rigid restriction of the sensitive period to the earlier 
part of larval life in the case of quercifolia suggested a set 
of transference experiments on the highly sensitive larva of 
Amphidasis betularia, carried out in the summer of 1896. The 
result was to prove that this species remains sensitive, at least 
to the strongest stimuli, viz. those provided by dark bark, for 
nearly the whole of larval life. 
