Naturalisation in Extra-Tropical Countries. 81 



Boswellia papyrifera, Hochstetter. 



Morocco Nubia and Abyssinia, forming entire forests about 

 Bertat on the Atlas. This tree exudes a kind of Olibanum-resin 

 and represents apparently one of the hardiest species of this or allied 

 genera. 



Boswellia serrata, Roxburgh. (B. thurifera, Colebrooke.) 



India. A deciduous tree, living in arid forest-regions. Yields an 

 aromatic resin. The real Olibanum is exuded by B. Carteri 

 (Birdwood) of Arabia and tropical Africa. 



Boussingaultia baselloides, Humboldt. 



South-America. This hardy climber is well fitted for bowers ; 

 the mucilaginous tubers are edible. It is not uncommonly grown 

 as a climber on verandahs, where no severe frosts occur. According 

 to Prof. Hieronymus the leaves serve in the native country of the 

 plant for spinage. 



Bouteloua polystachya, Torrey. 



New Mexico, Texas and Arizona. One of the Gramma-grasses 

 of the prairies, called with some other species also Muskit-grass ; 

 gregarious ; famed for nutritive value ; fit for arid regions. Dr. 

 Vasey recently enumerated fourteen kinds of Bouteloua, of which 

 B. foenea, B. eriopoda and B. oligostachya (Torrey) are mentioned 

 as those best liked by the herds ; the latter is known as the Blue 

 Gramma-grass ; B. curtipendula (Vasey) is the tall Gramma-grass ; 

 others proved excellent in Argentina. 



Bouvardia longiflora, Humboldt. 



Mexico, in temperate regions. This showy perennial shrub is not 

 without significance as a scent-plant. Cut flowers retain their odor 

 unusually long. One of the best of autumn-flowers. Thrives well 

 at Port Phillip. Referred to Houstonia now. 



Brabejum stellatifolium, Linne". 



South-Africa. The nuts of this usually small tree are edible, 

 resembling those of our Macadamia ternifolia, to which also Brabe- 

 jum is closely allied in foliage and flowers. The nuts are also 

 similar to those of the Chilian Guevina Avellana. The fruit should 

 be roasted, otherwise it is deleterious. Flowers sweet-scented. 



Brachychiton acerifolius, F. v. Mueller. 



The East- Australian Flame-tree. An evergreen shade- tree, attain- 

 ing a height of 60 feet, with magnificent trusses of crimson blossoms. 

 Like some congeners eligible for shading promenades, when rapidity 

 of growth is no object. The mucilaginous sap, when exuded, 

 indurates to a kind of Bassorin-Tragacanth, which Mr. J. H. Maiden 

 'dentifies with Pararabin and traces to other congeners as well as to 

 some Sterculias. 



