Let us sit down for a few minutes and watch its flight. How rapidly it flies, now pursuing the course of the river, now suddenly darting back again. It is the _Agrion virgo_, the most splendid of all the dragon-flies, even rivalling the gorgeously coloured insects of tropical countries. All the dragon-flies proceed from water larvae; strange creatures of unbecoming forms and ferocious dispositions. The mouth, or rather the lower lip of the larva is of very singular form. Two jaw-like organs are at the end of the lip, its basal portion being articulated to the head; this mask, as it has been called, is folded beneath the head when in repose, but it can be suddenly shot out in front of the head so as to seize any small creatures that may pass near it which the larva thinks good to eat. Imagine one of your arms being joined on to your chin, bend your elbow up till your hand covers your face--this will represent the dragon larva with the mask in repose; now shoot out your arm in a straight line from the head--this will represent the mask unfolded and in use; your fingers may be considered to represent the jaws of the creature. When the larva wishes to turn into an insect, it leaves the water and creeps up the stem of some water weed or other object out of the water, bursts its skin, and commences its new state of existence. If we look about us near the water side, we shall be sure to find some empty pupa skins. Here are two on this sedge; you see a slit on the back through which the dragon-fly has come out. The dragon-flies are the largest and most active of our British insects, and, to quote the descriptive words of Professor Rymer Jones, "are pre-eminently distinguished by the rapidity of their flight and the steadiness of their evolutions while 'hawking' for prey in the vicinity of ponds and marshy grounds, where in hot summer weather they are everywhere to be met with. Equally conspicuous from their extreme activity, their gorgeous colours, and the exquisite structure of their wings, they might be regarded as the monarchs of the insect race. The very names selected for them by entomologists would testify the perfection of their attributes; their titles ranging from that of _Anax imperator_, indicative of imperial sway, to epithets expressive of feminine delicacy and ladylike grace, such as _virgo_, _puella_, _demoiselle_, and _damsel-fly_, which are appropriated to the sylph-like forms that many of them exhibit. In their habits, however, they by no means deserve the gentle appellations bestowed upon them. They are, in truth, the tigers of the insect world, and their whole lives are devoted to bloodshed and rapine. Indomitable in their strength of wing, furnished with tremendous jaws, and possessed of acuteness of sight and rapidity of motion scarcely to be paralleled, there seems to be no escape from their ferocity, and terrible is the slaughter they effect amongst the insect legions they are appointed to destroy." It