But those are by no means the only dangers. It is not till the apple blossom, which has escaped all those perils, opens in the spring time, after its petals have unfolded in the warm air and the young apple is already half formed, that the Codlin Moth begins to attack them. This tiny little moth is then extremely busy. She lays about fifty eggs, but only one on each young apple. It is put in the one weak spot of the apple, just at the top, in the base of the withered flower. The grub tunnels down to the core and feeds upon the seeds, which are entirely destroyed. When it has grown sufficiently, it drives another tunnel straight outwards to the skin. If the apple is still on the tree, the caterpillar lets itself down on a long silken thread and hurries off to hide in any convenient crack or crevice of the bark, or if the apple is already stored away, it conceals itself in the walls or in the flooring of the loft. The moths come out at the end of next May, just when the blossoms are getting ready for them. These codlin-moth apples cannot fail to have been noticed by the reader, as the tunnels in the ripe apple are most conspicuous. The gradual fattening of the caterpillar can also be traced, for its first tunnel down to the seeds is quite narrow, while the way out gets wider and wider as the creature became stouter and fatter whilst eating its way through the flesh. The Pear Midge attacks at the same place, but the mother insect has a long egg-laying tube, and puts from fifteen to thirty eggs into the opening pear blossom. The pears go on growing, but of course are quite spoilt by the maggots within. These latter have a curious springing or jumping habit, and when they reach the soil bury themselves an inch or two below the surface. So that all the care and neatness with which the young flowers and buds are packed up goes for nothing, and these insect pests get all the benefits of the apple and pear! Besides these, there are hundreds of sorts of caterpillars which devour the leaves bodily. Cabbage-white butterflies, magpie-moths, gipsy-moths, diamondback-moths, and others, lay their eggs in hundreds. Many lay 300 eggs each. In the United States, somebody had sent an entomologist a present of some eggs of one of these moths. They were placed on a paper near a window which happened to be open; the entomologist went out, and the paper must have blown across the street into a garden on the other side. At any rate, two or three years afterwards it was found that some trees were badly attacked by this moth. Nobody thought much about this, though of course it was interesting to find a new moth. But the pest became a very serious one. In consequence of the stimulating air of the United States the moth multiplied with the most extraordinary rapidity, and it is said that about 300,000 dollars was spent in one year in the attempt to stamp it out. All this happened because an entomologist forgot to lock up his eggs when he went away for half an hour!