GUIDE TO INSECTS. 



Order COLEOPTERA. 



The insects of this Order are called Beetles. They have a 

 complete metamorphosis. The head is imbedded in the prothorax, 

 which is very large. The front wings, called elytra, are not used 

 in flight, but are hard and serve as covers to the hind wings, 

 which are folded in a complex manner beneath them. When at 

 rest they meet in a straight line down the back and do not cross 

 one another. 



They are commonly divided into twelve Sub- Orders, the principal 



characters for distinguishing which are explained by drawings and 



Table- specimens arranged in a tabular form in Table-case 51. These 



51-54 Sub-Orders are again divided into many families, a few of which 



are illustrated in Table-cases 52, 53 and 54. A series of specimens 



will be found in drawers of a cabinet on the east side of the 



gallery. 



The larvse are generally soft-bodied grubs living in concealment 

 Series of specimens illustrating the metamorphoses of Melolontha 

 (1 29), Propomacrus (1 31 ), Oryctes (1 35), Stenodontes (1 37), Spondylus 

 Wall- (139), and Aspidomorplia (143) are shown in Wall-case 8. 



Some problems connected with the geographical distribution of 

 animals are suggested by beetles arranged upon maps placed on the 

 West wall. 



The commoner British Beetles are shown in a cabinet on the 

 west side of the gallery, and a selected series of exotic representatives 

 of the Order is contained in cabinets on the east side. 



Some of the principal families of beetles are the following : 



The Cicindelidw are exceedingly active predaceous beetles, of 

 which the British species are known as Tiger-beetles. Their larvae 

 form perpendicular shafts in dry soil, and lie in wait to prey upon 

 passing insects. Some of the tropical forms are arboreal and the 

 larvse of Collyris make their tunnels in the twigs of shrubs by boring 

 a hole, through which they remove the pith. 



The CaralidoR, Ground Beetles, are predaceous, most of them 

 foraging by night, and lying hidden by day under stones, in 

 crevices, etc. A remarkable exception to this rule is Zabrus giblus, 

 which eats the ears of corn. Several genera, e.g., Brachinus and 

 Pheropsophus, have the power of extruding a drop of volatile and 

 explosive fluid by which they disconcert their pursuers, whence their 



