PLATE I. 



A CATERPILLAK (Cassus ligniperda). 

 (After Lyonet.) 



Fig. 4. Caterpillar opened on the ventral middle line. Fig. 5. Caterpillar opened on the dorsal 

 middle line, i, principal longitudinal tracheae ; 2, central nervous system ; 3, aorta ; 4, longi- 

 tudinal dorsal muscles ; 5. longitudinal ventral muscles; 6, wings of the heart ; 7, trachea! trunks 

 arising near spiracles ; 8, reproductive organs; 9, vertical muscles; 10, last abdominal spiracle. 



