84 



ASTRAGALUS LA.XMANNI. 



It does not appear so hardy as some of the other species, for the last winter 

 destroyed most of the plants in the garden. 



From this genus of plants (which comprehends upwards of 250 different 

 species) is obtained the gum tragacanth of commerce. For some years it was 

 considered to be the produce of the A. tragacantha, on the authority of Tourne- 

 fort, who visited Mount Ida and Mount Lebanon ; but La Billardiere, who after- 

 wards travelled in the same places, found that Tournefort had been mistaken, 

 and that the gum tragacanth was not collected from A. tragacantha, but from a 

 different species, to which he gave the name of A. gummifer. A subsequent 

 traveller, Mr. Olivier, who has since visited the East, affirms that the gum is not 

 collected for commerce from either of the above species (unless it be in very 

 small quantities), but that the bulk of what is sold in the markets is obtained 

 from a species entirely new, and to which he has given the name of A. verus. 

 There is no doubt, however, that all the above species, as well as A. creticus and 

 perhaps some others, afford more or less of that peculiar gum denominated 

 tragacanth, and which chemical analysis has shown to consist almost entirely of 

 pure cerasin. The power of this gum to render water viscid, is about twenty-four 

 times as great as that of gum-arabic. It is employed medicinally as a demul- 

 cent, and enters into the composition of various lozenges and other confectionary. 

 The gum exudes in summer, more or less copiously, according to the heat of the 

 weather, in tortuous filaments, which are allowed to dry on the plants before 

 they are collected. — " A. tragacanthoides is esteemed among the Kalmucs as a 

 febrifuge ; and a decoction of A. exscopus is said to afford great relief in the 

 distressing nocturnal pains of chronic rheumatism, and those which accompany 

 certain other cachectic disorders." 



The seeds of a few, as of A. Boeiica, are, like those of Phaca Boetica, roasted 

 and ground in some places, instead of coffee, for which purpose the plant is cul- 

 tivated in Sweden and Siberia. The seeds of A. cicer are used as food for chil- 

 dren, and also as forage for horses. The roots of A. aboriginorum, which are 

 long and yellow, like liquorice, are, in Arctic America, where it is a native, col- 

 lected as an article of food by the Crees and Stone Indians ; the roots of A. 

 Ammodgtes, which are also sweet, are used in Siberia instead of liquorice. The 

 leaves of A. glgcgphyllus have a sweetish taste when first chewed, which soon 

 changes to a nauseous bitter ; hence this plant, although indigenous here, is left 

 untouched by cattle. 



Fig. 1, the 5-toothed calyx; 2, the diadelphous stamens; 3, the legume; 

 4, the same, showing its inferior, introflexed suture. 



