ASTRAGALUS VERUS. 
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Tragacantha of Linnjeas, or the Astragalus Gummifera ; the former 
on the authority of Tournefort, and the latter on that of M. de la 
Billardiere.* It is probable that all these species afford the gum 
more or less, but the Astralagus Verus in much the largest quantity. 
The gum exudes, in summer,t through the bark, and concretes 
into irregular lumps, or long vermicular pieces, bent into an endless 
variety of shapes, and larger or smaller in proportion to its quantity, 
and the size of the wounds from which it issues. The quantity of 
Tragacanth furnished by Persia is very considerable, it is exported 
to India, Bagdad, and Bussorah, and also to Russia by the way of 
Bakon ; what is imported into this country comes chiefly from 
Aleppo, packed in cases. 
This is a low tree, seldom exceeding three feet in height ; the 
stem is about an inch in diameter ; the branches numerous, and 
crowded together, and covered with imbricated spines and scales, 
formed of the petioles of the preceding year ; the leaves are pinnate, 
consisting of six or eight pairs of leaflets ; the pinnze are nearly op- 
posite, villous, stilF, and pointed ; the flowers are small, and of a 
yellow colour, and arise from the axilla of the leaves ; the calyx is 
divided at the brim into five pointed segments ; the corolla is of the 
papiHonaceous kind. 
Sensible and Chemical Properties. Gum Tragacanth j: 
when good is inodorous, and as it dissolves in the mouth imparts a 
slight bitter taste : the best gum is semi-transparent, and of a clear 
whitish colour, and in small, thin, wrinkled, vermicular pieces or 
lumps ; the larger lumps are of a yellowish colour, and more bitter 
* He says, that he visited Mount Lebanon in August 1786, the season when the 
gum tragacanth is collected ; he then found the species of Astralagus which afforded it, 
to be different from that figured by Tournefort, and conseqijiently not the Tragacantha 
of Linnaeus. See description d'une nouvelle espece d'astragale, qui produit au Liban 
la goinrae adragant, Hist, de I'Acad. R. des Scien. du 16 Dec. 1788. 
The Genus Astralagus comprises a very numerous family of plants, natives of almost 
every climate and soil, sixty of which have been introduced and cultivated in our 
botanic gardens. — Hort. Canth. Four species of this genus are indigenous to Britain, 
viz. Astragalus Glycyphyllos, Astragalus Hypoglottis, Astragalus Uralensis, Astragalus 
Campestris. — Smith. 
t Tournefort says, that it exudes more or less copiously, according to the heat of 
the weather. M. de la Billardiere however contradicts this opinion, and says that it 
is only daring the night when the sun is obscured by clouds, that the gum issues from 
the plant. 
X Dr. John has given the name of Cerasin to this species of gum, from its being 
exuded from the Prunus Cerasus, (cherry tree.) 
