LEPIDOPTERA. 



43 



imperfectly developed, except the maxillae which (except in a few 

 cases) are greatly prolonged and united by their edges to form a 

 proboscis or tube (through which moisture can be drawn into the 



Fig. 43. 



a 



Head of a Sphinx moth showing the parts of the mouth and proboscis, 

 a, Eye ; b, labial palpus ; c, maxillse ; d, maxillary palpus on base of maxilla. 



mouth), coiled like a watch-spring when at rest. The labial palpi 

 are well developed, usually standing up in front of the head, 

 sometimes of great length. The maxillary palpi are generally very 

 small or absent, except in the most primitive family Micropterygidw, 

 where they are well developed. 



