23 



The trees yielding rubber commercially all belong to one of 

 the three orders — Apocynace&\ Euphorbiaceae or Urticaceas 

 while the one yielding the "Chicle" gum belongs 

 Sapotaceae. These plants 

 arranged : — 



Alstonia plumosa (Labill) 

 Castilloa elastica (Cerv) 

 Chilocarpus viridis (new sp.) 

 Ficus elastica (Roxb) 

 „ Vogellii (Mig) 

 Fosteronia floribunda (G. F. W. 



Mey) 



Fosteronia gracilis (Muell) 

 Hevea braziliensis (Muell) 

 Leucanotis eugenifolia (A..D.C.) 

 Landolphia florida (Bth) 



„ Kirkii (Dyer) 



,, Owariensis (Beauv) 



,, Petersiana (D)er) .. 



Manihot Glaziovii (Muell) 

 Sapium Aucuparium (Jacq) 

 Willughbea flavescens (Dyer) . . 

 Achras sapota (Linn) 



are as follows, 



'• Fiji rubber" .. 



" Central American" 



" Assam rubber" 

 " Liberian rubber " 



" West Indian rubber' 



" Para rubber " 



" African rubber" 



"Ceara Scrap" 



" Colombian rubber 



Chicle Gum ! 



to the order 

 alphabetically 



Apocynaceae. 



Urticaceae. 

 Apocynaceae. 



Urticaceae. 



Apocynaceae. 



>> 

 Euphorbiaceae. 

 Apocynaceae. 



Euphorbiaceae. 



Apocynaceae. 

 Sapotaceae 



From the foregoing list we may, I think, delete the following 

 for the present, as the plants are not sufficiently known as sources 

 from which rubber may be obtained, or the trees are not likely to 

 be suitable to our climate, though one or more of them may yet 

 be tried here, if reports as to their suitability for the purpose 

 should prove to warrant it. They are as under : — 



Alstonia plumosa, Chilocarpus viridis, Ficus Vogellii, 

 Fosteronia floribunda and gracilis, Leaucanotis eugenifolia, 

 Sapium Aucuparium and Willughbea flavescens. The remainder 

 I will take in alphabetical order : — Castilloa elastica (Cerv), a 

 native of Central America, which yields what is known as 

 " Central American Rubber." In 1875, Mr. Robert Cross was 

 sent by the India Office to obtain seeds of this tree ; some 7,000 

 seeds were sent to Kew, but all failed to germinate. Mi*. Cross 

 then despatched a large number of cuttings which were pro- 

 pagated at Kew, and sent to the West coast of Airica, Ceylon and 

 Java. From Ceylon the late Dr. Trimen reported that the plant 

 required a more tropical climate than that of Peradiniya, and the 

 plants were removed to a lower elevation at Heneratgoda. In 

 1880 Dr. Trimen reports : Our largest trees at Heneratgoda have 

 now a circumference of nearly 17 inches, at a yard from the 

 ground. In October, 1882, the same writer reports : — " We have 

 some sturdy little seedlings coming on from seed. The rubber 

 from Castilloa strikes me as the most satisfactory sort growing 

 here, the proportion of caoutchouc in the milk being larger than 

 in any of the others." As to the yield, Mr. Cross, a competent 

 authority, says ; — "A Castilloa tree, if carefully and judiciously 



