This is the bark of Cornus Florida, or common dogwood, a small indigenous tree, remarkable for its conspicuous white flowers, which render it one of the finest ornaments of our forests in the spring, as its glossy-red fruit, and leaves beautifully tinted by the frost, do in the autumn. The bark is taken indiscriminately from the root, stem, and branches; but that of the root is preferred. It is in pieces of various size, partially or completely rolled, sometimes with and sometimes without epidermis, of a reddish-gray colour, a feeble odour, and a bitter, astringent, slightly aromatic taste. It is brittle, and yields a gray, slightly reddish powder. Either water or alcohol will extract its virtues. These probably reside in a peculiar bitter principle, which, however, has not yet been isolated; for neither the cornin of Mr. Carpenter, nor the substance used, under the same name, by the eclectic physicians, so called, can be admitted to this rank. The bark contains also tannic acid, but not in sufficient proportion to give it any considerable medicinal activity.

The effects of dogwood on the system, so far as they can be traced, are those of a mild tonic and feeble astringent. It is said to increase the strength and frequency of the pulse, and the heat of the body; but, so far as known, it produces none of those effects upon the brain which characterize the action of Peruvian bark. In the recent state, it is said to act unkindly on the stomach and bowels; but, in this respect, it resembles most other tonics, when too freely administered.

Dogwood has been used almost exclusively, as a substitute for Peruvian bark, in the treatment of intermittent and remittent fevers; and, from the amount of testimony in its favour, there can be no doubt that it often has proved efficacious in the former of these complaints. But it has often also failed; and, since the introduction of sulphate of quinia into use, has been little employed by regular practitioners.

It may be used in powder or decoction. The dose of the powder in intermittents is stated at a drachm, so repeated as to amount to one or two ounces between the paroxysms. The U. S. Pharmacopoeia directs a decoction (Decoctum Cornus Floridae, U. S.) to be made by boiling an ounce, in a pint of water, for fifteen minutes, then straining, and adding enough water, through the strainer, to make the decoction measure a pint. The whole pint may be taken in one intermission, in doses of two fluidounces. An extract, prepared with water or alcohol, might he substituted for either of the above forms with advantage. The profession is indebted chiefly to Dr. John M. Walker, who published a thesis on dogwood, in Philadelphia, in the year 1803, for what is known upon the subject.

The bark of two other indigenous species of Cornus, 0. circinata or round-leaved dogwood, and C. sericea or swamp dogwood, have similar sensible properties, and are supposed to have the same medical virtues as that of C. Florida.