io6 



INSECT TRANSFORMATION 



and a series of elongate, flexible teeth adorns its inner 

 border ; its sharply pointed apex, covered with sensory hairs, 

 projects beyond the front edges of the tongue and labium. 

 Maxillulae have now been recognized 1 in larvae of beetles of 

 several families. 



Larvae of the general aspect just described are seen also 

 among other families of beetles. The rotund, somewhat 

 flattened carrion-beetles species of Silpha (Fig. 58 a) for 

 example have larvae that are typically onisciform, not only 

 resembling wood-lice in appearance but being as large as some 

 of those interesting if familiar Crustacea. The Silpha grub 

 (Fig. 58 b) has fairly long and prominent feelers, but these 



a 



FIG. 58. 



a, CARRION BEETLE (Silpha opaca). x 3. 

 Carpenter, " Life Story of Insects ". 



6, larva of Silpha, x 4. From 



consist of four segments only ; the maxilla (Fig. 59 b) has a 

 three-segmented palp, a small but distinct hairy galea, and a 

 spinose lacinia. Though also onisciform, these Silpha larvae 

 do not approach the adult in their minute structure so closely 

 as do the little helodine larvae. But on the whole all these 

 beetle grubs that we have so far considered with their well- 

 developed exoskeleton and relatively long legs may be 

 regarded as differing less than most insect larvae from their 



1 A. M. Evans : " On the Structure and Occurrence of Maxillulae in the 

 Orders of Insects". Journ. Linn. Soc. (Zoo/.), XXXIV. 1921. 



