The same author recommends as a remedy against ants, which are by no means the slightest plague in a garden that is not kept well watered, to stop up the mouths of their holes with sea-slime or ashes. But the most efficient way of destroying them is with the aid of the plant heliotropium;[1233] some persons, too, are of opinion that water in which an unburnt brick has been soaked is injurious to them. The best protection for turnips is to sow a few fitches with them, and for cabbages chickpeas, these having the effect of keeping away caterpillars. If, however, this precaution should have been omitted, and the caterpillars have already made their appearance, the best remedy is to throw upon the vegetables a decoction of wormwood,[1234] or else of house-leek,[1235] known to some as “aïzoüm,” a kind of herb already mentioned by us. If cabbage-seed, before it is sown, is steeped in the juice of house-leek, the cabbages, it is said, are sure not be attacked by any insect. It is said, too, that all caterpillars may be effectually exterminated, if the skull[1236] of a beast of burden is set up upon a stake in the garden, care being taken to employ that of a female only. There is a story related, too, that a river crab, hung up in the middle of the garden, is a preservative against the attacks of caterpillars. Again, there are some persons who are in the habit of touching with slips of blood-red cornel[1237] such plants as they wish to preserve from caterpillars. Flies,[1238] too, infest well-watered gardens, and more particularly so, if there happen to he any shrubs there; they may be got rid of, however, by burning galbanum.[1239] (11.) With reference to the deterioration to which seed is subject,[1240] there are some seeds which keep better than others, such, for instance, as that of coriander, beet, leeks, cresses, mustard, rocket, cunila, nearly all the pungent plants in fact. The seed, on the other hand, of orage, ocimum, gourds, and cucumbers, is not so good for keeping. All the summer seeds, too, last longer than the winter ones; but scallion seed is the very worst for keeping of them all. But of those, even, which keep the very longest, there is none that will keep beyond four years—for sowing[1241] purposes, at least; for culinary purposes, they are fit for use beyond that period. CHAP. 59.—WHAT PLANTS ARE BENEFITTED BY SALT WATER.