THE DRAGON-FLIES. 201 



black veins_, and the long slender abdomen is of a 

 light azure-blue^ with a patch at the hinder margin, 

 and a line on the side of each segment black, and the 

 last two or three segments entirely of that colour. 

 The graceful appearance of these gauze-winged crea- 

 tures as they hover lightly about under the brilliant 

 summer sky, and settle as gently as a flake of down 

 upon the leaves which fringe their abode, must be 

 viewed with admiration by every one, but they are 

 far exceeded in splendour by some allied exotic 

 species, whose wings exhibit a brilliancy of metallic 

 colouring scarcely exceeded in the insect world. A 

 few species with coloured mngs also occur in this 

 country, and one of them, the Calepteryx Virgo, is 

 not uncommon along our slow rivers. It measures 

 upwards of two inches in length, and has a long 

 cylindrical abdomen of a fine steel-blue or greenish 

 blue colour, and large brown Avings which often ex- 

 hibit strong metallic violet tints. 



In their preparatory states, which are always 

 passed in the water, these insects are engaged in a 

 perpetual war of destruction with the weaker inha- 

 bitants of their domain, and although the larvae and 

 pupae are exceedingly sluggish animals, they are fur- 

 nished with a peculiar apparatus of prehension, which 

 renders them formidable, not only to worms and 

 the larvae of other insects which might be expected 

 to fall an easy prey to such marauders, but even to 

 small fishes and other creatures, whose activity it 

 might be supposed would have enabled them to keep 

 out of danger. The prehensile organ consists of the 

 lower lip, which, although presenting a considerable 

 analogy in its structure with the labium of the per- 

 fect insect, has all its parts greatly elongated, but so 



k5 



