110 



NATURE SKETCHES IN TEMPERATE AMERICA 



The Protected Schizuea 

 Caterpillar 



'OW well protected certain insects are 

 from the keen vision of predaceous 

 birds and other higher animals is well 

 jgi exemplified in the Schizura ipomecB 

 caterpillars. 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 

 Hymenoptera, which have a form of 

 vision different to that of the birds. I 

 present herewith two photographic re- 

 productions of one of these moth cater- 

 pillars. The photographic plate caught 

 the caterpillar 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-rib of the leaf, where it remained 

 motionless. In the first position this 

 caterpillar's form was most diflBcult 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 identifying 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 of 

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



