110 



NATURE SKETCHES IN TEMPERATE AMERICA 



The Protected Schizura 

 Caterpillar 



( )W well protected certain insects are 

 troni the keen vision of predaceous 

 t)irds and other higher animals is well 

 exemplified in the Schizura ipomeoe 

 ( ukrpillars. During exposure in day- 

 time and while feeding on leaves, this 

 simulation of the surroundings is of 

 paramount importance in their preser- 

 vation. However, it may not preserve 

 them from the attacks of the small 

 Ilymenoptera, which have a form of 

 vision different to that of the birds. I 

 I resent herewith two j)liotographic re- 

 j)r()(iuctions of one of these moth cater- 

 j)illars. The photographic i)late caught 

 the cateri)illar while feeding on a half- 

 eaten dogwood leaf. The initial photo- 

 graph shows the same individual which, 

 having taken alarm and stopped its feed- 

 ing process, had backed off along the 

 mid-ril) of the leaf, where it remained 

 motionless. In the first position this 

 caterj)illar's form was most difficult to 

 make out. Its brown and green body 

 presented the exact counterpart of a 

 withered brown blotch on the dogwood 

 leaf. Moreover, this resemblance was 

 so perfect that the scrutiny of several uninformed persons, 

 who were asked to examine it, failed in itlentifying it. 



This deception is brought about by the adaptation of both 

 form and color. The back or dorsal outline, being formed 

 into tubercles and elevations, gives to the larva the effect cf 

 being part of the eaten leaf itself, with an irregularly excavated 



