The root of Aristolochia reticulata Nutt., a plant of Louisiana and Arkansas, has been brought into commerce in considerable quantity as Texan or Red River Snake-root.[2224] We are indebted for an authentic specimen from the Cherokee country to Mr. Merrell, a large dealer in herbs at St. Louis, Missouri, who states that all the serpentary grown south-west of the Rocky Mountains is the produce of that species. The late Prof. Parrish of Philadelphia was kind enough to supply us with specimens of the same drug, as well as with reliable samples of true Virginian or Middle States Snake-root.
The Texan snake-root is somewhat thicker and less matted than that derived from A. Serpentaria, but has the odour and taste of the latter; some say it is less aromatic. The plant, portions of which are often present, may be easily distinguished by its leaves being coriaceous, sessile and strongly reticulated on their under surface.
CUPULIFERÆ.
CORTEX QUERCUS.
Oak Bark; F. Ecorce de Chêne; G. Eichenrinde.
Botanical Origin—Quercus Robur L., a tree, native of almost the whole of Europe, from Portugal and the Greek Peninsula as far north as 58° N. lat. in Scotland, 62° in Norway, and 56° in the Ural Mountains.
There are two remarkable forms of this tree which are regarded by many botanists as distinct species, but which are classed by De Candolle[2225] as sub-species.
Sub-species I. pedunculata—with leaves sessile or shortly stalked, and acorns borne on a long peduncle, and acorns either sessile or growing on a short peduncle.
Sub-species II. sessiliflora—with leafstalks more or less elongated.
Both forms occur in Britain. The first is the common oak of the greater part of England and the lowlands of Scotland. The second is frequently scattered in woods in which the first variety prevails, but it rarely constitutes the mass of the oak woods in the south of England. In North Wales however, in the hilly parts of the north of England, and in Scotland, it is the commoner of the two forms (Bentham).