124 



INSECTS. 



we get those giants of their race, the elephant and goliath beetles, which are 

 nearly as big as a man's fist, and the still larger titan from South America, 

 which is sometimes quite half a foot long, and scarcely less broad in proportion. 

 Even within the limits of a single species beetles are not always of a nearly 

 uniform size ; and it is not uncommon to find that in certain species some 

 individuals may be very much larger than others, frequently two or three times 

 as large, and occasional^ even as much as five times. In their external form 

 beetles also afford the most striking contrasts ; and the differences of form are not 

 confined to the general shape but extend to nearly all parts of the body. The 

 head especially varies to a great extent both in its shape and in the direction 

 which it takes. It is somewhat ring-like behind, where it fits more or less deeply 

 into the cavity of the prothorax. The part between the eyes and the prothorax 

 may be as wide as or even wider than the rest of the head, or may be abruptly or 

 l 2 s 



CARNIVOROUS BEETLES AND THEIR PREY. 



1, Carabus nemoralis ; 2, Calosoma sycophanta ; 3, Carabus auratus, and larva. (All nat. size.) 



gradually narrowed behind to form a sort of neck. In most beetles this part of 

 the head is rather short, but its length varies ; and there is one remarkable species 

 from the Philippines which presents a most comical appearance owing to the 

 extraordinary length of its neck. This species belongs to a group of leaf-rolling 

 beetles, and doubtless finds its long neck extremely useful. The fore-part of the 

 head is most variable in shape, and though generally short is in some beetles quite 

 out of all proportion in its length. In the weevils it is prolonged in the form of a 

 rostrum or snout, which is sometimes much longer than all the rest of the body. 

 What is called the " front " of the head frequently faces upwards, being on the 

 same plane, or nearly so with the occiput or posterior part of the upper surface. 

 But in many beetles the fore-part of the head is bent down, so that the front looks 

 forwards ; and sometimes even to such an extent that the mouth is drawn back 

 against the prothorax, and the front of the head looks downwards. The lower or 

 anterior part of the front of the head is called the clypeus, and to this — usually by 



