24 



SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I43 



adaptations for procuring, consuming, and digesting an abundance of 

 food, and for storing a surplus for the pupa and the adult. The fact 

 that some moths have found it unnecessary to eat at all in the adult 



Fig. 12. — Geometridae. 



A, Caterpillars of the spring cankerworms Paleacrita vernata. B, Female 

 moth of spring cankerworm laying eggs. C, Successive locomotor phases of a 

 geometric! caterpillar ; a, distance advanced with each extension after looping. 



stage would seem to attest the efficiency of the caterpillar as a provider 

 for the whole life span of the individual. The only organs not 

 particularly involved in the adaptive specialization of the caterpillar 

 are the heart, the tracheal system, and the nervous system in its 

 gross structure. 



