There are few creatures, again, which one would so little suspect of any attempt to bully and bluff others as the soft-bodied caterpillars. They are as a rule so plump and squashy and defenceless: a mere peck from a bird's beak is enough to kill them, for when once their tight, thin skin is broken, were it but with a pin-prick, all the flabby contents burst out at once in the messiest fashion. Yet even caterpillars, strange to say, have their tricks of terrifying. They pretend to be dangerous characters. I will set out with some of the simplest and least developed cases, and then pass on to a more complex and wily class of deceivers. To begin with, I must premise that two sets of caterpillars have two different ways of evading the unpleasant notice of birds and other insect-eaters. One way is that adopted by the common "woolly-bear," a great hairy caterpillar, frequent in gardens, and covered from head to tail with long needles or bristles. These prickly points make the creature into a sort of insect hedgehog; birds refuse to touch him, because the serried spikes, which to us are mere hairs, seem to them perfect spines or thorns, sticking into their tongues and throats, or clogging their gizzards. Protected caterpillars like the woolly-bears live quite openly, exposed on the leaves and branches of their food-plant; they are not afraid of being seen: nay, they rather court observation than shun it, because they know nobody will attack them. The porcupine has no need to run away like the rabbit. Similar tactics are also adopted by many nasty-tasting caterpillars, in whose bodies natural selection has developed bitter or unpleasant juices. These caterpillars are rejected by birds and lizards--the great enemies of the race--and therefore they find it worth while to clothe themselves in gaudy and conspicuous red or yellow bands, so as to advertise all comers of their inedible qualities. Whenever you see such brilliantly-attired grubs (like those of the Magpie Moth, so common on gooseberry-bushes--a striking creature tricked out in belts of black and orange), you may be sure of two things: first, they live openly and undisguisedly on the leaves of their food-plant, without any attempt at mean concealment; and second, they are nasty to the taste, and therefore rejected as food by insect-eating animals. Now and then a young and inexperienced bird may eat one, to be sure; but it never tries twice, and the solitary martyr is sacrificed for the good of the race. Their bright colours and gaudy bands are just advertisements, as it were, of their inedible qualities. For, of course, nasty taste would do a caterpillar no good if the bird had always to sample it before rejecting it; the broken skin alone would be enough to kill it. Hence almost all uneatable caterpillars have acquired bright colours by natural selection--that is to say, by the less bright being continuously devoured or killed; and birds on their