part i

. (1869) 94.

The dried fruit differs slightly from the ordinary prune in being rather larger and more elongated, and having a thicker skin; also in the stone being flatter, narrower, pointed at either end, with the ventral suture much more strongly curved than the dorsal. The fruits seem rather more prone to become covered with a saccharine efflorescence.

CORTEX PRUNI SEROTINÆ.

_Cortex Pruni Virginianæ_; _Wild Black Cherry Bark_.

=Botanical Origin=—_Prunus serotina_ Ehrhart (_P. virginiana_ Miller non Linn., _Cerasus serotina_ DC.)—A shrub or tree, in favourable situations growing to a height of 60 feet, distributed over an immense extent of North America. It is found throughout Canada as far as 62° N. lat., and from Newfoundland and Hudson’s Bay in the east, to the valleys west of the Rocky Mountains.[966] It is also common in the United States.

The tree is often confounded with _P. virginiana_ L., from which, indeed, it seems to be separated by no fixed character, though American botanists hold the two plants as distinct. It is also nearly allied to the well-known _P. Padus_ L. of Europe, the bark of which had formerly a place in the Materia Medica.

=History=—Experiments on the medicinal value of Wild Cherry Bark were made in America about the end of the last century, at which time the drug was supposed to be useful in intermittent fevers.[967] The bark was introduced into the _United States Pharmacopœia_ in 1820. An elaborate article by Bentley[968] published in 1863 contributed to bring it into notice in this country, but it is still much more employed in America than with us.

=Description=—The inner bark of the root or branches is said to be the most suitable for medicinal use. That which we have seen is evidently from the latter; it is in flattish or channelled pieces, ⅒ to ¹/₂₀ of an inch in thickness, ½ an inch to 2 inches broad, and seldom exceeding 5 inches in length. From many of the pieces, the outer suberous coat has been shaved off, in which case the whole bark is of a deep cinnamon brown; in others the corky layer remains, exhibiting a polished satiny surface, marked with long transverse scars. The inner surface is finely striated, or minutely fissured and reticulated. The bark breaks easily with a short granular fracture; it is nearly without smell, but if reduced to coarse powder and wetted with water it evolves a pleasant odour of bitter almonds. It has a decided but transient bitter taste.

The bark freshly cut from the stem is quite white, and has a strong odour of bitter almonds and hydrocyanic acid.

[966] Hooker, _Flora Boreali-Americana_, i. (1833) 169.

[967] Schöpf, _Materia Medica Americana_, Erlangæ 1787; 77.—Also Barton, _Collections for Mat. Med. of U.S._, Philad. 1798. 11.

[968] _Pharm. Journ._ v. (1864) 67.—Also Bentley and Trimen, _Med. Plants_,