3S2 



2OOLOO1 . 



so considerable that it passes backwards beyond the p<> 

 extremity of the abdomen. 



In the flies the proboscis, sometimes soft and retractile, some- 

 times horny and elongated, represents also the lower lip, and 



often carries feelers on its 

 basis ; a longitudinal groove 

 occupies the superior sur- 

 face and lodges the stylets, 

 whose number varies from 

 two to six, and whose ana- 

 logues in the bruising or 

 grinding insects are the manr 

 dibles, the jaws, and the 

 languette or little tongue. 

 Sometimes this proboscis ac- 

 quires an enormous length 

 (Fig. 362), sometimes, on 

 the contrary, it is scarcely 

 visible. 



524. Finally, in the 

 butterflies (Fig. 364), which 

 are also nourished on liquid 

 substances, but which are 

 found at the bottom of 

 flowers, and which have no 

 occasion for cutting or pierc- 

 ing instruments to obtain 

 them, there no longer exist 

 stylets performing the func- 

 tions of lancets, as in the 

 preceding, and the mouth is 

 furnished with a long pro- 

 boscis (c d, Fig. 363), rolled 

 into a spiral; and composed 

 of two filaments, hollowed 

 into a groove on their 

 inner surface, which are 

 nothing but jaws extremely 

 elongated and modified in their shape. At the base of this 

 proboscis we distinguish anteriorly a small membranous 

 piece, which is the representative of the labium or lip, 

 and on each side a small tubercle, the last vestige of the 

 mandibli-s. We observe also here the rudiments of the 



Fig. 362. Nemeatrina longirostris. 



