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TEXT-BOOK OF ENTOMOLOGY 



Mandibles are wanting in the adults of the more specialized Lepi- 

 doptera, being vestigial in the most generalized forms (certain 

 Tineina and Crambus), but well developed in that very primitive 

 moth, Eriocephala (Fig. 51). They are also completely atrophied in 

 the adult Trichoptera, though very large and functional in the pupa 

 of these insects (Fig. 52), as also in the pupa of Micropteryx (Fig. 53). 



FIG. oO. : Mandible of <ipri Carolina. After Smith. A'C. an</glt/j>ticus. A (fipmv u> right), 

 do. of Leiitotrophus cingulatus; , of Phanasus carnifex; g', end of galea, g, enlarged; 

 c, conjunctivus. C, of Meloe angusticollis : I, lacinia ; a, lacinia enlarged. 



They are also wanting in the imago of male Diptera and in the 

 females of all flies except Culicidae and Tabanidae. 



They are said by Dr. Horn to be absent in the adult I'Juti/jmt/Uus 

 raxforis, though well developed in the larva; and functional mandi- 

 bles are lacking in the Hemiptera. 



The first maxillae. These highly differentiated appendages are 

 inserted on the sides of the head just behind the mandibles and the 

 mouth, and are divided into three lobes, or divisions, which are sup- 

 port < d upon two, and sometimes three basal pieces, i.e. the basal 



