On this account, if any considerable area be involved, it is a mistake to attempt to treat the whole of it at once, as such a course may easily result in producing an amount of soreness and inflammation which may involve confinement to bed. The patches should be attacked piecemeal, a couple of separate patches the size of a shilling being quite as much as is prudent to attack on any one occasion. Equal parts of tincture of iodine, carbolic acid and glycerine painted over each patch, to the extent above described, is a safe and efficient remedy, as also is Goa powder; but the essential point is to be on the look-out for the contingency, and to at once treat any patch that may appear before it has time to spread. The disease is, I believe, common enough in other warm climates, but I am not acquainted with its popular designation elsewhere than in India, where it is known by the above name. ON THE PREVENTION OF DISEASES CAUSED BY INTERNAL WORMS. _Internal worms_ are extremely common in most hot countries, and especially in those climates where moisture and heat are combined. Where they prevail to a serious extent, they often constitute one of the principal causes of mortality amongst natives, but white residents rarely suffer, as the habits of the better-class European to a very great extent protect him from being invaded by these pests. There are three principal sorts of these parasites: the round-worms, which usually divide their time between some animal and the outer world, and the flat-worms and the flukes, both of which must pass through two or more animal hosts. The life-history of these troublesome guests, especially those belonging to the two latter classes, include some of the most wonderful and interesting pages of natural history, but unfortunately considerations of space prevent our describing these changes except by the barest allusions. The commonest round-worms that establish themselves in mankind are the common thread-worms and round-worms (_Lumbrici_), and that much more formidable pest of tropical life, the _Ankylostoma_, or hook-worm. Thread-worms and Lumbrici are common enough everywhere, but are far more commonly troublesome in hot climates than at home in Europe. The eggs of both are probably usually carried into the human intestine on food or in drinking water, and in the case of the Lumbricus this is the only way in which the numbers of the parasite can be maintained, as its eggs take a long time to hatch out; but those of the thread-worm, when deposited, are quite ready to burst at once, and though no individual worm as a rule resides within the intestine for any great length of time, the patient infested with them is continually reinfecting himself, so that their numbers have a tendency to increase. Thread-worms are especially common in children, on account of the strong tendency of the little folks to put their fingers in the mouth.