THE ANATOMY OF IXSECTS. 



less convex, and their mesal surface concave. Usually each mandible consists 

 of a single segment; but in some insects these organs are much more com - 

 plicat 



In several genera of Rove-beetles {StapkyHnida] each mandible is furnished 

 with an appendage (Fig. 23). This was named the prostheca by Kirby and 

 Sper 



FIG. 23. Mandible of Staphylinus. 



Fig. 24. Mandible of Euphoria inda. 



In many beetles of the family Scarabaeidae each mandible consists of s< 

 more or less distinct sclerites. This is \vel. shown in the mandible of Euphoria 

 . . These compound mandibles have not yet been studied with 

 sufficient care to enable us to definitely name the parts. 



The axillae (11) are the more ventral of the two pairs of 



are much more complicated than the mandibles, each maxilla 

 consisting, when all of the parts are present, of five primary parts and thn 

 pend._ The primary parts are the cardo or hinge, the stipes or footstalk, 

 tne / r palpus-bearer, the subgalea or helmet-bearer, and the lacii.. 



blade. The appendages are the maxillary palpus or feeler, \\\z.galea or sup< 

 lobe, and the digitus or finger. The maxilla may also t >th- 



like projectio: . bristles, and hairs. 



In the following description of the parts of the maxillae, only very gem ral 



s can be made. Not only is there an infinite variation in the form of 



parts, but the same part may \\. v different outline on the dorsal 



aspect of the maxilla from what it has on the ventral. Compare Fig. 25 and 



i represent the two aspects of the maxilla of Hyiirophilus. Except - 



; ires of maxillae represent the ventral aspect of this organ. 



-Ventral aspect of 

 ,aof Hyd>, 



Dorul 

 maxilla of /tfJrefkilnt. 





\illa. It is 



of les tri. ll the part upon v- ; 



of the motions of this or:;. any cases, however, it is not the 



