670 PROBOSCIS OF LEPIDOPTERA. 



reaches the orifice of the tube formed by the approximation of the 

 maxillfe above, and of the labial palpi and this part of the ligula 

 below." 



520. By the plan of conformation just described, we are led to 

 that which prevails among the Lepidoptera or Butterfly tribe, and 

 which, being pre-eminently adapted for suction, is termed the 

 Eaustellate mouth. In these Insects, the Labrum and Mandibles 

 are reduced to three minute triangular plates ; whilst the Maxillse 

 are immensely elongated, and are united together along the median 

 line to form the Haustellium or Proboscis, which contains a tube 

 formed by the junction of the two grooves that are channelled-out 

 along their mutually applied surfaces, and which serves to pump-up 

 the juices of deep cup-shaped flowers, into which the size of their 

 wings prevents these Insects from entering. The length of this 

 Haustellium varies greatly : thus in such Lepidoptera as take no 

 food in their perfect state, it is a very insignificant organ ; in some 

 of the white Hawk-Moths, which hover over blossoms without 

 alighting, it is nearly two inches in length ; and in most Butter- 

 flies and Moths it is about as long as the body itself. This Haus- 

 tellium, which, when not in use, is coiled-up in a spiral beneath 

 the mouth, is an extremely beautiful Microscopic object, owing to 

 the peculiar banded arrangement it exhibits (Fig. 345), which is 



Fig. 345. 



Haustellium (proboscis) of Vanessa. 



probably due to the disposition of its muscles. In many instances, 

 the two halves may be seen to be locked together by a set of 

 hooked teeth, which are inserted into little depressions between the 



