CHAPTER XII 



THE BEETLES (COLEOPTERA) 



Characteristics. Fore-wings, horny or leathery, forming wing-covers (elytra), 

 which meet in a straight line down the back ; hind-wings, membranous, tips 

 folded back under the wing-covers when at rest ; mandibulate mouth-parts ; 



metamorphosis, complete. 







The hard wing-covers of this order are so characteristic that a 

 beetle is commonly recognized as such, and they have given the 



FIG. 189. A water-scavenger beetle with wing-covers and wings expanded 



as when in flight. (Natural size) 



(After Folsom) 



order its scientific name, from coleos (a sheath) and pteron (a 

 wing). The beetles form one of the largest orders, with over twelve 

 thousand species in America north of Mexico, belonging to some 

 eighty families, only the most common of which will be mentioned. 

 They have a complete metamorphosis, the larvae being commonly 

 called grubs, and the pupae are usually found either in the ground 



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