At first sight it might seem as though there were hardly enough of such pungent and fiery things in existence to make it worth while for us to be provided with a special mechanism for guarding against them.  That is true enough, no doubt, as regards our modern civilised life; though, even now, it is perhaps just as well that our children should have an internal monitor (other than conscience) to dissuade them immediately from indiscriminate indulgence in photographic chemicals, the contents of stray medicine bottles, and the best dried West India chilies.  But in an earlier period of progress, and especially in tropical countries (where the Darwinians have now decided the human race made its first debut upon this or any other stage), things were very different indeed.  Pungent and poisonous plants and fruits abounded on every side.  We have all of us in our youth been taken in by some too cruelly waggish companion, who insisted upon making us eat the bright, glossy leaves of the common English arum, which without look pretty and juicy enough, but within are full of the concentrated essence of pungency and profanity.  Well, there are hundreds of such plants, even in cold climates, to tempt the eyes and poison the veins of unsuspecting cattle or childish humanity.  There is buttercup, so horribly acrid that cows carefully avoid it in their closest cropped pastures; and yet your cow is not usually a too dainty animal.  There is aconite, the deadly poison with which Dr. Lamson removed his troublesome relatives.  There is baneberry, whose very name sufficiently describes its dangerous nature.  There are horse-radish, and stinging rocket, and biting wall-pepper, and still smarter water-pepper, and worm-wood, and nightshade, and spurge, and hemlock, and half a dozen other equally unpleasant weeds.  All of these have acquired their pungent and poisonous properties, just as nettles have acquired their sting, and thistles their thorns, in order to prevent animals from browsing upon them and destroying them.  And the animals in turn have acquired a very delicate sense of pungency on purpose to warn them beforehand of the existence of such dangerous and undesirable qualities in the plants which they might otherwise be tempted incautiously to swallow.

In tropical woods, where our ‘hairy quadrumanous ancestor’ (Darwinian for the primaeval monkey, from whom we are presumably descended) used playfully to disport himself, as yet unconscious of his glorious destiny as the remote progenitor of Shakespeare, Milton, and the late Mr. Peace—­in tropical woods, such acrid or pungent fruits and plants are particularly common, and correspondingly annoying.  The fact is, our primitive forefather and all the other monkeys are, or were, confirmed fruit-eaters.  But to guard against their depredations a vast number of tropical fruits and nuts have acquired disagreeable or fiery rinds and shells, which suffice to deter the bold aggressor.  It may not be nice to get