The leaves of B. crenulata afforded us upon incineration 4·7 per cent. of ash. Jones (1879) obtained on an average 4·54 per cent. from the same species; 5·27 from B. serratifolia; and 4·49 from B. betulina. He pointed out the presence of manganate in this ash.
The Diosmin of Landerer[435] is entirely unknown to us.
Commerce—The export of buchu from the Cape Colony in 1872 was 379,125 lb., about one-sixth of which quantity was shipped direct to the United States.[436]
Uses—Buchu is principally administered in disorders of the urino-genital organs. It is reputed diuretic and diaphoretic. In the Cape Colony the leaves are much employed as a popular stimulant and stomachic, infused in water, sherry, or brandy. They are also extensively used in the United States, both in regular medicine and by the vendors of secret remedies.
Substitutes—The leaves of Empleurum serrulatum Ait., a small shrub of the same order as Barosma and growing in the same localities, have been imported rather frequently of late and sold as Buchu. They have the same structure as regards mucilage, and nearly the same form as those of B. serratifolia, but are easily distinguished. They are still narrower, and often longer than those of B. serratifolia, devoid of lateral veins, and terminate in an acute point without an oil-duct. They have a bitterish taste and a less powerful odour than those of Barosma, even in fresh leaves as imported in London. The odour of Empleurum is moreover distinctly different from that of the leaves of Barosma. The flowers of Empleurum are still more distinct, for they are apetalous and reddish-brown. The fruit consisting of a single, compressed, oblong carpel, terminated by a flat-shaped horn, is quite unlike that of buchu.
The leaves of Barosma Eckloniana Berg (regarded by Sonder[437] as a form of B. crenulata) have to our knowledge been imported on one occasion (1873). They are nearly an inch long, oval, rounded at the base, strongly crenate, and grow from pubescent shoots.
We have seen other leaves which had been imported from South Africa and offered as buchu; but though probably derived from allied genera they were not to be mistaken for the genuine drug.
RADIX TODDALIÆ.
Botanical Origin—Toddalia aculeata Pers., a ramous prickly bush,[438] often climbing over the highest trees, common in the southern parts of the Indian peninsula as the Coromandel Coast, South Concans, and Canara, also found in Ceylon, Mauritius, the Indian Archipelago and Southern China.
History—The pungent aromatic properties which pervade the plant, but especially the fresh root-bark, are well known to the natives of India and have been utilized in their medical practice. They have also attracted the attention of Europeans, and the root of the plant is now recognized in the Pharmacopœia of India.