A. M. Altson 



189 



and in the act of biting, and their function is, apparently, crushing the 

 food — in the later instars the particles of wood tissue — whilst the setae 

 strain or align it, before it passes into the pharynx. 



mt mi 



Fig. 1 



.^i,',pr 



^P la 



F^g-5 



Text-fig. 1. 



ng.6 



The labrum (Text-fig. 1, 2 a) is clearly defined and is sparsely fringed 

 with very fine bristles. The clypeus and epistome were not discernible, but 

 the anterior border of the frons (fn) is strongly defined and appears as 

 a stoutly chitinised semi-circular rod (hr) supporting the upper region of 



