92 



TRANSFORMATIONS OF INSECTS. 



change in the butterfly must be determined in the chrysalis 

 state, and during the progress of the second metamorphosis. It 

 has been proved that the duration of the chrysalis condition 

 can be lengthened by placing the pupa in cold and dark places, 

 or in ice, and shortened by increasing the usual amount of warmth. 

 But no variation in the ornamentation of the perfect insect has 

 been produced by this artificial lengthening or shortening of 

 chrysalis life. So that most probably the disposition of these 

 butterflies to vary has some deep significance, which refers to the 

 duration of the species in time — moribund genera and species 

 varying much, and new forms striving to adapt themselves to 

 peculiar conditions. 



The hybernation of some of the large butterflies through the 

 winter in temperate climates is very interesting. 





