The leaves of argel after a little practice are very easily recognized; but their complete separation from senna by hand-picking is a tedious operation. They are lanceolate, equal at the base, of the same size as senna leaflets but often larger, of a pallid, opaque, greyish-green, rigid, thick, rather crumpled, wrinkled and pubescent, not distinctly veined. They have an unmistakeably bitter taste. The small, white, star-like flowers, or more often the flower buds, in dense corymbs are found in plenty in the bales of Alexandrian senna. The slender, pear-shaped follicles, when mature 1½ inches long, with comose seeds are less frequent. It has been shown by Christison[850] that argel leaves administered per se have but a feeble purgative action, though they occasion griping. It is plain therefore that their admixture with senna should be deprecated.
The leaves or leaflets of several other plants were formerly mixed occasionally with senna, as those of the poisonous Coriaria myrtifolia L., a Mediterranean shrub, of Colutea arborescens L., a native of Central and Southern Europe, and of the Egyptian Tephrosia Apollinea Delile. We have never met with any of them.[851]
FRUCTUS CASSIÆ FISTULÆ.
Cassia Fistula; Purging Cassia; F. Casse Canefice, Fruit du Caneficer; G. Röhrencassie.
Botanical Origin—Cassia Fistula L. (Cathartocarpus Fistula Pers., Bactyrilobium Fistula Willd.) a tree indigenous to India, ascending to 4000 feet in the outer Himalaya, but now cultivated or subspontaneous in Egypt, Tropical Africa,[852] the West Indies and Brazil. It is from 20 to 30 feet high (in Jamaica even 50 feet) and bears long pendulous racemes of beautiful fragrant, yellow flowers. Some botanists have established for this tree and its near allies a separate genus, on account of its elongated, cylindrical indehiscent legume, but by most it is retained in the genus Cassia.
History—The name Casia or Cassia was originally applied exclusively to a bark related to cinnamon which, when rolled into a tube or pipe, was distinguished in Greek by the word σῦριγζ, and in Latin by that of fistula. Thus Scribonius Largus,[853] a physician of Rome during the reigns of Tiberius and Claudius, with the latter of whom he is said to have visited Britain, a.d. 43, uses the expression “Casiæ rufæ fistularum” in the receipt for a collyrium. Galen[854] describing the different varieties of cassia, mentions that called Gizi[855] (γίζεις) as being quite like cinnamon or even better; and also names a well-known cheaper sort, having a strong taste and odour which is called fistula, because it is rolled up like a tube.
Oribasius, physician to the Emperor Julian in the latter half of the 4th and beginning of the 5th century, describes Cassia fistula as a bark of which there are several varieties, having pungent and astringent properties (“omnes cassiæ fistulæ vires habent acriter exalfacientes et stringentes”), and sometimes used in the place of cinnamon.[856]
It is doubtless the same drug which is spoken of by Alexander Trallianus[857] as Κασίας σῦριγζ (casia fistula) in connexion with costus, pepper and other aromatics; and named by other Greek writers as Κασία συριγγώδης (casia fistularis). Alexander still more distinctly calls it also Κασία αἰγυπτία.[858]
The tree under examination and its fruit were exactly described in the beginning of the 13th century by Abul Abbâs Annâbatî of Sevilla;[859] the fruit, the Cassia Fistula of modern medicine, is noticed by Joannes Actuarius, who flourished at Constantinople towards the close of the 13th century; and as he describes it with particular minuteness,[860] it is evident that he did not consider it well known. The drug is also mentioned by several writers of the school of Salernum. The tree would appear to have found at an early period its way to America, if we are correct in referring to it the Cassia Fistula enumerated by Petrus Martyr among the valuable products of the New World.[861] The drug was a familiar remedy in England in the time of Turner, 1568.[862]
The tree was figured in 1553 by the celebrated traveller Belon who met with it in the gardens of Cairo, and in 1592 by Prosper Alpinus who also saw it in Egypt.