MAXILLA. 253 



Burmeister, bears at its extremity the maxillary palpus (mp) : 

 the internal or dorsal piece (la piece dorsale of Strauss- 

 Diirckheim, b) occupies the space between this and the 

 membrane which runs parallel therewith, forming the basal 

 part of the internal terminal lobe (d). Conjointly, these 

 three pieces (b, c, and d) are termed the stipes or stalk of 

 the maxillae by MacLeay and Kirby. The last of these, or 

 the fourth piece of the maxillae (d), is more important, ex- 

 tending not only along the internal side of the maxillae, 

 but also often considerably beyond the former pieces, and 

 being very variable in its form : its terminal portion (d d) 

 has been named the internal lobe of the maxillae by MacLeay 

 and others, but it is not distinct from the basal part (d). 

 In the predaceous beetles 

 it is long, slender, curved 

 at the tip, and internally 

 clothed with fine hairs or 

 bristles, and sometimes 

 terminated by a hook, 

 which is either entire, as 

 in Carabus, or articulated, 

 as in the tiger-beetles (fig. 

 102). This part is termed 

 la piece intermaxillaire 

 by Strauss - Diirckheim, 



and lacinia by MacLeay. In some biting insects it is of a 

 very large size, as in the bees, in which it forms the sole 

 terminal lobe of the maxillse (fig. 103). In many instances, 

 however, it is greatly reduced in size, not extending beyond 

 the base of the palpus, in which case another organ is de- 

 veloped at its expense, which, as in the large water-beetle 

 (Hydrous piceus), joins the terminal part of the maxillae 

 (figs. 99, 100, 101 e). In the predaceous beetles this ex- 



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