We have so often repeated the officinal title of this medicine, that we may be excused for adopting here, at the close, the simple name which preceded all the others, and will probably survive them. There seems, in the influence of mercury, something even more noxious for the lower grades of animals than for man. in Magendie's Journal de Physiologie Expérimentale (i. 105) is an account of experiments by M. Gaspard, which prove the extraordinary incompatibility of the mercurial influence with insect life. it is well known that solutions of corrosive sublimate, of very moderate strength, are among the most effective poisons for the animals that infest the exterior of the body. The biniodide of mercury is said to be still more effectual. it seems also that they are equally poisonous to the parasites of the interior, when they can be brought into contact with them. Küchenmeister found the roundworm to be killed by corrosive sublimate in from one to two hours. But the difficulty is to bring these soluble salts of mercury into contact with the worms in the small intestines, without administering them so largely as to be hazardous to the patient. The same is not the case exactly with the threadworm, upon which they can be brought to bear directly. Trousseau and Pidoux have found injections of the biniodide and bichloride of mercury extremely effective in ascarides of the rectum. To an adult they administer, two or three days successively, an enema consisting of a quart of water, in which five centigrammes (about three-fourths of a grain) of the biniodide are dissolved, by means of one-tenth of iodide of potassium, or they use the same quantity of corrosive sublimate without, such addition. To children only one-fourth or one-fifth of this quantity is given. They have rarely failed of success. They advise the repetition of the remedy a fortnight afterwards, and another repetition at the end of four or five weeks. {Trait, de Thérap., etc., 4e ed., i. 209.)

* Slippery Elm Bark. Dr. J. R. Dowler, of Beardstown, Illinois, having found that a child, who had chewed and swallowed portions of slippery elm bark, discharged sections of tapeworm, and having afterwards obtained the same effect repeatedly from the use of the same means, was convinced that he had found an efficient anthelmintic in this bark, and subsequently used it successfully in the case of an adult affected with the same disease. Dr. Dowler is probably right in believing that the remedy acted mechanically, the worm being alive when discharged. [Boston Med. and Surg. Journ., March 10, 1865, p. 132.) - Note to the third edition.

Calomel has long enjoyed great reputation as an anthelmintic against the roundworm; and it is certainly among the most efficacious. On the tapeworm it produces little effect. it is possible that, as slowly dissolved through the agency of the chlorides in the bowels, it may act on the worm directly with a poisonous influence; but it has probably also another mode of action. Every physician must have noticed that, in attacks of bilious vomiting and purging, or of bilious diarrhoea alone, roundworms, if existing in the bowels, are apt to be evacuated. it is probable that they are poisoned, or rendered uncomfortable and debilitated, by the same irritant influence of the morbid bile which causes spasm of the stomach and bowels, with cholera or diarrhoea, in man. Now calomel is characterized by the abundance of the bilious discharges which it provokes, and these, too, not unfrequently of a highly irritant character it is probable, therefore, that it acts as a vermifuge mainly through the acrid bile, the production of which it stimulates. Adding this effect to its poisonous action as a mercurial, and its purgative operation, we can well understand how the medicine should have obtained the reputation it has long possessed in this respect.

Calomel is given as an anthelmintic in the ordinary purgative doses. (See vol. II. p. 561.) it is most conveniently administered at bedtime, and followed by a dose of castor oil in the morning, so as to insure its action on the bowels. it is peculiarly adapted to infantile cases, and may with great propriety be given with spigelia, or any other ordinary vermifuge.

The above list of anthelmintics includes the most effective remedies belonging to this class; but it might be greatly extended; for there is a very large number of substances, possessed of more or less vermifuge power, which have been and still are occasionally used. Among these may be particularized olive oil, castor oil, croton oil, black hellebore, gamboge, colocynth, scammony, and cevadilla, belonging to the cathartics; quassia, wormwood, and tansy, to the tonics; assafetida, valerian, and garlic, to the nervous stimulants; camphor, to the cerebral stimulants; tobacco and peach leaves, to the nervous sedatives; creasote and petroleum, to the stimulating diuretics; and rue, Savine, and our native Juniperus Virginiana, to the emmenagogues. Among mineral substances, the powder of tin and iron filings, which act mechanically, and lime-water, common salt, tartar emetic, sulphate of iron, and arsenious acid, which are supposed to poison the worms, may also be added to the catalogue. Almost all of these have been treated of in different parts of this work, and their supposed anthelmintic virtues incidentally referred to.

Under the name of kameela or reroo, a medicine was a few years since brought to the notice of the Western world from India, where it was in use as a powerful vermifuge, being considered especially efficacious in tapeworm. it is obtained from a euphorbiaceous plant called Rottlera tinctoria, and consists of a powder mixed with hairy spicula brushed off from the outer surface of the fruit. it is of a dark-reddish colour and peculiar heavy odour, and when swallowed operates as a cathartic, and in large doses as an emetic. The reports in its favour, made by the British army surgeons in India, have in some degree been confirmed by the experience of physicians in England; but it has scarcely yet come into such extensive use, or acquired a reputation so well established, as to merit a place among our standard remedies. Some doubts have existed whether it simply expels, or positively kills the worm; but the weight of testimony is in favour of the latter mode of action. it is used extensively as a remedy against the tapeworm. From one to four drachms of the powder may be given to an adult; or a tincture may be prepared with four ounces of the powder to a pint of alcohol, and given in the dose of from one to four fluidrachms.