234 • INSECTS ABROAD. 



granulated ; there is a flattish edge on the sides, and on either- 

 side of the suture is a long and prominent ridge. The long legs 

 are flattened, especially the thighs of the hind legs. Each elytron 

 has a curved and very sharp spike on the shoulder, so that the 

 Eeetle has a sufficiently formidable aspect. 



The jaws are flat, powerful, strongly curved, and each is armed 

 near the tip with a double tootli. Their colour is black, and the 

 surface is finely granulated. 



Most of the Prionidse are dull-coloured, but there are one or 

 two exceptions. Such, for example, is Psalidognaihus Friendii, a 

 native of Columbia. This insect is exceedingly variable. Some 

 are brown, others blue, and others deep purple, while many 

 specimens exhibit both colours. They also differ in size, some 

 being one-third less than others, while some of them have their 

 elytra shaped differently from those of their relatives. 



When the Prionus larva is full fed, it encloses itself in a 

 cocoon made of little strips of the timber in which it has lived ; 

 and, after the manner of all tunnelling insects, it always under- 

 goes its transformation close to the bark of the tree, so that when 

 it assumes its perfect shape, it may find its way out of the tunnel 

 with as little difficulty as possible. For the perfect Beetle is 

 much wider than the larva, and not so flexible, so that, in spite 

 of the very powerful jaws with which it is armed, it would not 

 be able to force its way through the narrow channel which it 

 had formerly occupied. 



The large species to which reference has been made is Prionus 

 giganteus, a Brazilian Beetle. Its eggs are remarkable for their 

 size, far exceeding in dimensions those of many humming-birds ; 

 and indeed, but for their shape, which is much elongated and 

 similar at both ends, they might well be taken for the eggs of a 

 bird, and not of an insect. In order to place their eggs securely, 

 the ovipositor of some of the species is provided with a curious 

 apparatus much resembling two short spears set side by side, 

 each spear-head being furnished with one or more knobs on 

 the outside, apparently for the purpose of fixing the apparatus 

 while the egg slides along it. The larva of one of the large 

 exotic Prionidse is used for food, and in all probability many 

 such larvae are edible, though they do not particularly suit 

 our own ideas of delicacies. 



