CAOUTCHOUC OF ECONOMIC PLANTS. 89 



7. Madagascar Eubber is the produce of Landoliphia gum- 

 mifera, a large climber of the same family as the preceding, 

 with opposite, smooth, elliptical, blunt leaves ; the flowers are 

 large, white, and produced in cymes ; the fruit is round or pear- 

 shaped, filled with granular pulp, with bean-like seeds ; the stems 

 contain a quantity of Caoutchouc of very good quality. 



8. Cryptostegia grandiflora, a climber of the Swallowwort 

 family (Asclepiadacese), native of India. Its milky juice con- 

 tains Caoutchouc, but, although the plant is very common, it is 

 doubtful whether its collection would pay. 



9. Mangava or Mangabeira, a BraziKan name for Hancornia 

 speciosa, a small tree of the Dogbane family (Apocynacese), 

 having drooping branches, with small oblong leaves. The flowers 

 are sweet -smelling; the fruit is a large globular fleshy berry, 

 with numerous seeds, and, like the whole plant, exuding a milky 

 juice ; it is wholesome, and considered by the Brazilians a 

 delicious fruit. The milk of the tree when exposed to the air 

 hardens, and becomes Caoutchouc. In 1880 the importation of 

 India-rubber from all sources amounted to 166,459 cwts. 



Many other plants might be noticed producing Caoutchouc, 

 but as most of them are of small size, as compared to those 

 mentioned, the collection requires much time, and not being 

 remunerative, they are therefore neglected. Of late years the 

 great demand for India-rubber and the destruction of trees to 

 obtain it has led the Indian Government to endeavour to intro- 

 duce the American Caoutchouc trees into India, which has been 

 successfully accomplished during the last few years by the 

 exertions of Mr. Eobert Cross, who in 1875 was sent to America 

 for plants of Castilloa clastica. These were brought to Kew, 

 where they were fully established and propagated, and ulti- 

 mately sent to Ceylon and India, where they are thriving ; and in 

 1876 Mr. Cross was despatched to the Amazon for plants oiRevea 

 hrasiliensis, 1000 of which were also brought to Kew, together 

 with plants of the Ceara scrap rubber, which, with the preceding, 

 are now flourishing in Ceylon and India. It is therefore prob- 

 able that in time these trees wiU be yielding rubber in such 



