THE HIDDEN TYPE OF WING-GROWTH in 



of the chafer grub is usually bent like a bow, the dorsal aspect 

 convex ; this attitude is appropriate to the creature's habit 

 of lying in an underground chamber feeding on roots. The 

 head is large and prominent with a hard, firm, rounded capsule, 

 bearing fairly elongate, four-segmented feelers and strong 

 mandibles which possess not only well-developed apical biting 

 teeth and basal grinding areas, but also, on their hinder 

 aspect, ridged or tuberculate patches known as " stridulat- 

 ing organs " which produce a shrill sound when rubbed across 

 by the strong teeth on the maxillary stipes. The maxilla of 

 a chafer-grub has the typical parts well denned, though there 

 may be partial union of the lacinia with the galea. Vestiges 

 of maxillulae have been detected on the front aspect of the 



FIG. 62. 



a, Garden Chafer (Phylloperthahorticola), dorsal view; 6, larva, 

 side view, x 3. From Carpenter, Econ. Proc. R. Dublin Soc. II. 



tongue. The legs are prominent and hairy, remarkable for the 

 excessive proportional length of the haunch, the thigh and 

 shin being much abbreviated, while the foot-claw is extremely 

 reduced in length on the third leg of the cockchafer grub and 

 on the second leg of the larva of the garden chafer. In the 

 larva of one of the dor-beetles (Geotmpes) which belong to 

 the same family (Scarabaeidae) as the chafers, the legs are 

 clawless and those of the third pair are very short and feeble 

 in comparison with the others. In larvae of the allied tropical 

 Passalidae, which live and feed in timber, the first and second 

 pairs of legs are typical in structure while those of the third 

 pair are exceedingly short, thickened and armed with rows 



