ORDER LEPIDOPTERA 



53 



Leaf-mining influences the shape of the head-capsule no 

 less than the form of body and the development of legs. 

 In free-living caterpillars, the three principal parts which 

 make the head-capsule, namely, the right and left sides and 

 the front, are separated from one another by a Y-shaped 



Fig 22 Alteration of form of head capsule and mouth parts m leaf- 

 mining caterpillars. (After Traegardh.) A and B, head capsules of two 

 sap-feeding leaf -miners, Lithocolletis and Phyllocmstis respectively: letter- 

 ing as before. C, the head of an ordinary caterpillar, face view; /, frons; 

 a, a, adfrontal pieces; e, e, epicronial plates, separated by an epicranial 

 suture; 1, labrum partly covering the mandibles; t, t, antennae. D, head 

 capsule (appendages omitted of a tissue-feeding leaf-miner, Aphelosetia. 

 The frons reaches backward to the rear margin between the prolonged 

 epicronial plates. 



