554 Select Plants for Industrial Culture and 



species are extant as far as their fruits are concerned. No attempts 

 seem as yet to have been made, to improve the fruits of any Vaccinium 

 by hybridizing nearly allied species under horticultural care. We 

 would like to see any one of the kinds, alluded to in these pages, 

 naturalised on the Australian Alps. 



Vahea Comorensis, F. v. Mueller. (Landolpliia florida, Bentham.) 



East- and West-Africa, up to 2,500 feet. This may prove hardy 

 in mild extra-tropic regions. Dr. Welwitsch describes the Aboh- 

 fruit of this species as sweet and acidulous, but was not less gratified 

 with the beauty and marvellous abundance of its large snow-white 

 and jasmin-scented flowers. V. Comorensis also yields much caout- 

 chouc, like V. Heudelotii (Landolpliia Heudelotii, D.C.) from the 

 Senegal regions. The genus Vahea was fully established by Lamarck 

 as early as 1791. The excellent work on the caoutchoucs of com- 

 merce, by James Collins, may be consulted as regards the sources of 

 various kinds of India-rubbers. Prof. Wiesner ("'RohstoSe des Pflan- 

 zenreichs," 1873) enumerates at p. 154-156 the various plants, then 

 known to yield caoutchouc, giving also a chemical account of these 

 substances. Professor Schumann (in "Engler's Botan. Jahrbiicher," 

 1892, p. 401) devotes an excellent article to the Vaheas specially. 



Vahea Kirkii, J. Hooker. (Landolphia Kirkii, Dyer. ) 



Eastern Tropical Africa in mountain-regions. Professor Sadebeck 

 states that this species produces caoutchouc even superior to that 

 from V. Comorensis, and he adds as a new species V. Traunii as an 

 equally valuable plant from Western and Central Africa. The young 

 German colony in East Africa exported already in 1892 during nine 

 months caoutchouc to the value of 50,000 [" Deutsches Kolonial 

 Blatt," July, 1893]. 



Vahea Owariensis, F. v. Mueller. (Landolphia Owariensis, Beauvois.) 



Tropical West-Africa, but ascending to the. highlands of Angola, 

 according to Dr. Welwitsch. This climber, with several other 

 Vaheas, yields the West- African caoutchouc ; others furnish the 

 Madagascar-sort, particularly V. gummifera (Lamarck), now culti- 

 vated also in India. Prof. Wiesner of Vienna enumerates 47 species 

 of various genera, which yield either rubber, gutta percha or balata. 

 It is said that the addition of ammonia to the sap improves the rubber. 

 V. Owariensis produces edible fruits as large as middle-sized oranges, 

 with sweet and slightly acid pulp. 



Valeriaua Celtica, Linn. 



Alps of Europe ; hardy at Christiania. The " Speik." The root 

 of this perennial herb is particularly aromatic. 



