in Extra-Tropical Countries. 25 



Aloe ferox, Miller. 



South- Africa. This species yields the best Cape-aloes, as observed 

 by Dr. Pappe. The simply inspissated juice of the leaves of the 

 various species of the genus constitutes the aloe-drug. It is best 

 obtained by using neither heat nor pressure for extracting the sap. 

 By re-dissolving the aqueous part of Aloes in cold water, and reducing 

 the liquid through boiling or other processes of exsiccation to dryness, 

 the extract of aloes is prepared. The bitter sap, used for dressing 

 wounds, keeps off flies very effectually. It deserves introduction par- 

 ticularly in veterinary practice. All species are highly valuable, and 

 can be used, irrespective of their medicinal importance, to easily and 

 inexpensively beautify any rocky or otherwise inarable spot. 



Aloe linguiformis, Miller. 



South- Africa. According to Thunberg, the purest gum-resin is 

 obtained from this species. 



Aloe Perryi, Baker. 



Socotra. It is now known, that it was this species, which furnished 

 the genuine "Aloes," renowned in antiquity (Baker, Balfour). It 

 grows best in limestone-soil, and ascends to 3,000 feet. Flowers 

 turning from scarlet to yellow. Closely allied to A. vulgaris. 



Aloe plicatilis, Miller. 



South- Africa. The drug of this species acts more mildly than that 

 of A. ferox. 



Aloe purpurascens, Haworth. 



South- Africa. Another of the plants, which furnish the Cape-aloes 

 of commerce. The South- African Aloe arborescens (Miller) and A. 

 Commelyni (Willdenow) are also utilized for aloes, according to Bail- 

 Ion, Saunders and Hanbury. 



Aloe spicata, Thunberg. 



South- Africa. This also furnishes Cape-aloes, and is an exceed- 

 ingly handsome plant. 



Aloe vera, Miller. (A. succotritw, Lamarck.) 



South- Africa. A purplish flowered species, figured already by 

 Commelyn in 1697 (Baker). Yields the common Socotrine-aloes and 

 Moka-aloes. 



Aloe vulgaris, Bauhin. (A. vera, Linne"; A. JBarbadensis, Miller.) 



The Yellow-flowered Aloe. Countries around the Mediterranean 

 Sea, also Canary-Islands, on the sandy or rocky sea- coast. Such 

 places could also be readily utilized elsewhere for this and allied 

 plants. Dr. Sibthorp has identified this species with the AXo/ of 

 Dioscorides ; thus it is also the real Aloe of Plinius ; hence it is not 

 probable, that A. vulgaris is also simultaneously of American origin, 

 although it is long cultivated in the Antilles, and furnishes from 



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