in the wilder parts of Colorado you would find a close resemblance to Buffalo Bill was no mean personal protection.  Hornets, in fact, are insects to which birds and other insectivorous animals prefer to give a very wide berth, and the reason why they should be imitated by a defenceless beetle must be obvious to the intelligent student.  But while the vibrating wing-cases of this deceptive masquerader are made to look as thin and hornet-like as possible, in all underlying points of structure any competent naturalist would see at once that the creature must really be classed among the noisome Hemiptera.  I seldom trouble the public with a Greek or Latin name, but on this occasion I trust I may be pardoned for not indulging in all the ingenuous bluntness of the vernacular.

Sometimes this effective mimicry of stinging insects seems to be even consciously performed by the tiny actors.  Many creatures, which do not themselves possess stings, nevertheless endeavour to frighten their enemies by assuming the characteristic hostile attitudes of wasps or hornets.  Everybody in England must be well acquainted with those common British earwig-looking insects, popularly known as the devil’s coach-horses, which, when irritated or interfered with, cock up their tails behind them in the most aggressive fashion, exactly reproducing the threatening action of an angry scorpion.  Now, as a matter of fact, the devil’s coach-horse is quite harmless, but I have often seen, not only little boys and girls, but also chickens, small birds, and shrew-mice, evidently alarmed at his minatory attitude.  So, too, the bumble-bee flies, which are inoffensive insects got up in sedulous imitation of various species of wild bee, flit about and buzz angrily in the sunlight, quite after the fashion of the insects they mimic; and when disturbed they pretend to get excited, and seem as if they wished to fly in their assailant’s face and roundly sting him.  This curious instinct may be put side by side with the parallel instinct of shamming dead, possessed by many beetles and other small defenceless species.

Certain beetles have also been modified so as exactly to imitate wasps; and in these cases the beetle waist, usually so solid, thick, and clumsy, grows as slender and graceful as if the insects had been supplied with corsets by a fashionable West End house.  But the greatest refinement of all is perhaps that noticed in certain allied species which mimic bees, and which have acquired useless little tufts of hair on their hind shanks to represent the dilated and tufted pollen-gathering apparatus of the true bees.

I have left to the last the most marvellous cases of mimicry of all—­those noticed among South American butterflies by Mr. Bates, who found that certain edible kinds exactly resembled a handsome and conspicuous but bitter-tasted species ’in every shade and stripe of colour.’  Several of these South American imitative insects long deceived the very entomologists; and it was only by a close