ied tubers or root-stock of
_Ipomoea Jalapa_ or _Convolvulus Jalapa_, a perennial plant, native of
America. Some suppose it takes its specific name from Xalapa, in
Mexico, whence we chiefly import it. It grows in the woods near
Chicanquiaco, at an altitude of 6,000 feet above the level of the sea.
Large quantities might be gathered and exported in Jamaica. The root
is of a roundish tuberous form, black externally, and of a deep,
yellowish grey within, and varies in size from that of a walnut to
that of a moderate sized turnip. It contains a resin in which its
active properties reside. It is brought to this country in thin
transverse slices, and the amount entered for home consumption is
about 45,000 lbs. a year. It is imported in bales, from Vera Cruz
direct, or indirectly by way of New York, and other places.

Two sorts of jalap root occur in commerce. The one which was first
introduced into the market, and which is even at the present day most
frequently met with, is obtained from the _Ipomoea Schiedeana_ of
Zuccarini, a plant growing on the eastern declivity of the Mexican
Andes, and discovered by Von Schiedes. The root, as met with in
commerce, consists of pieces varying from the size of a nut to that of
the fist, sometimes whole, sometimes cut into disks, and at other
times divided into two or three portions. The external surface is of a
more or less dark gray brown color, corrugated and rough. It is very
hard, presents a shining resinous even surface when broken, and is
difficult to reduce to powder. The powder is of a brownish color, has
a faint peculiar odor and irritant taste.

The second quality, which was introduced into commerce is great
quantities a few years ago, by the name of stalk jalap, is now more
scarce, and obtained from the _Ipomoea orazabensis_ of Pelletan, a
plant growing without cultivation in the neighbourhood of the Mexican
town of Orizaba. The root, as met with in the trade, consists of
pieces varying from one to three inches in length, and 11/2 to two
inches in diameter. They are of a higher color than the first-named
root, and of decidedly fibrous structure. The chief constituents of
both varieties is a peculiar resin, of which they contain about 10 per
cent.

Scammony.--The root of _Convolvulus Scammonia_, another plant of the
same family, affords, when cut, a gummy resinous exudation or milky
juice, which soon concretes and forms scammony. The plant grows
abundantly in Greece, the Gre