THE TORTRICINA. IAI 
they lead very different lives. Their skin is shiny, soft, and 
frequently covered here and there with hairs which are exqui- 
sitely sensitive. They are of different colours ; the green tints, 
THE METAMORPHOSIS OF /Zalras quercana. 
however, predominate, and they are not perfectly white like those 
caterpillars that never see daylight. These Leaf Rollers usually 
undergo their metamorphoses in the tubes, folds, and packets of 
leaves which were formed by the caterpillars which shut up all 
the orifices with silken threads when they have attained their full 
