18 INSECTS ABROAD. 



detected by the eye alone, while the iiiuumerable cells of the 

 elytra cannot be seen without a microscope. 



The arrangement of these folds or wrinkles is w^orth notice. 

 A lin© runs along the centre of the head, from wliicli the 

 wrinkles sweep in curves on either side, much like the lines of 

 hair parted in the middle. Thus much can be seen with the 

 naked eye ; but if the microscope be used, it will be seen that 

 each wrinkle is regularly and elaborately waved throughout its 

 length, thus, ^^-^-.^^^^^^ ; so adding to the richness of the effect. 

 Still taking the human hair as our illustration, the waved 

 structure of these wrinkles produces a similar effect to that 

 which is obtained by ladies when they crimp their hair by 

 artificial means. 



I have already mentioned tliat the upper surface of this 

 magnificent insect is entirely covered with wrinkles or cells, so 

 as to give it a saiiny or velvety appearance. The violet under 

 surface is quite smooth, and looks like burnished metal, affording 

 a tine contrast to the softly brilliant hues of the upper surface. 

 The one dazzles and startles the eye, the other soothes and 

 satisfies it. The principle which is so perfectly carried out in 

 this insect is followed imperfectly by ourselves. Whe}i a draper 

 shows a piece of silk, satin, or velvet to a lady, he does not spread 

 it out flat, but gathers it into folds and artistic wrinkles. 



The reason is evident enough. Supposing that a yard of silk 

 or satin be spread flat, there is a certain amount of colour, with 

 a tolerably uniform distribution of light and shade. But, let 

 three yards of the same material be gathered into the same 

 space, it is evident that three times the amount of colour is 

 obtained, while each fold gives different gradations of hue 

 according to the depth of shades. This is one of the many 

 instances where man unconsciously borrows from Nature, and 

 complacently thinks that he has invented something quite new. 



Of the habits of this Beetle I know nothing by practical 

 experience, but the specimen which has been most imperfectly 

 described gives a curious proof that it must be quite as tierce as 

 our British Tiger Beetles. The jaws of this species are long, 

 sickle-sha,ped, deeply toothed on the inner edge, crossing each 

 other when closed, and very conspicuous from their shining yellow 

 colour. The jaws of this specimen are firmly closed, and hold in 

 tl)('ir griisj) lliG fore-leg of another I'eetle of the same species. 



