BOTANICAL INFORMATION. 153 



The inestimable truth, that we may safely calculate on the closest affi- 

 nities of the medicinal properties of plants with their natural alliances 

 a truth which achieved the most complete triumph of the Natural System 

 over all artificial classifications — has generally guided me in tracing out 

 which plants might be administered in medicine. By this guidance I 

 observed, that our Pimelem are pervaded by that acridity for which the 

 bark of Daphne Mezereum is employed ; that our Polygala veronicea, the 

 only described Australian species of a large genus, and in close relation 

 to one lately discovered in the Chinese empire, not only agrees, like some 

 kinds of Comesperma^ with the Austrian Polygala amara^ in those qua- 

 lities for vvhich that plant has been administered in consumption, but 

 also participates in the medicinal virtue of Polygala Senega^ from North 

 America. Gratiola latlfoUa and Gratiola piibescenSy Conviilvulm eru- 

 bescens, and the various kinds of Mentha^ are not inferior to similar 

 European species. The bark of Tasmania aromatica appears to me to 

 possess the medicinal power of the ff^irdera bark, gathered from a similar 

 tree in Tierra del Fuego ; and its fruit is allied to that of the North 

 American Magnolm used in cases of rheumatism and intermittent fever. 

 The whole Natural Order of Goodeniacece, with the exception, perhaps, 

 of a few species, contains a tonic bitterness never recognized before, 

 and discernible in many plants in so high a degree, that I was induced, 

 for this reason, to bestow upon a new genus from the interior the name 

 of Picrophyta ; this property, which indicates a certain alliance to Gen- 

 tianece, deserves the more consideration, as the true Oentianem are so 

 sparingly distributed through Australia, while the Goodeniacecc form 

 evei-yvvhere here a prominent feature in the vegetation. Our Alps, 

 however, enrich us also with a thick-rooted Gentian {G, Diemoish), 

 certainly as valuable as the officinal Gentiaiia liitea ; and in the spring, 

 Sabrea ovata, Sahcea alhidifiora, and Erythrcjea australis, might also be 

 collected on account of their bitterness. The bark of the Australian 

 Sassafras-tree {Alherospermum vioscJiatuvi) has already obtained some 

 celebrity as a substitute for tea : administered in a greater concentra- 

 tion, it is diaphoretic, as well as dinretic, and has for this reason al- 

 eady been practically introduced into medicine by one of om- eminent 

 physicians. laotoma axillaris surpasses all other indigenous LobeUacets 

 in its intense acridity, and can be therefore only cautiously employed 

 instead of Lobelia inflata. The root of Malva Behriana scarcely differB 

 from that of Altluen officinal, and the Salep-root might be collected 



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