1838.] Report on the Caoutchouc Tree of Assam. 139 



There is every reason for supposing that this tree presents every 

 facility for multiplication by division, and probably the plan pursued by 

 the natives with the peepul will be effectual for this purpose : a branch is 

 chosen of the thickness of a man's thigh, and of a height of 15 or 20 

 feet ; all its branches with the exception of one or two at the apex are to 

 be lopped off clean, and the wounds to be plastered over with clay. The 

 cutting is to be planted out at the commencement of spring, that is in 

 March or April*. 



The jangal must be cleared, but not so much so as to expose the cut- 

 tings to the full influence of the sun. It must be borne in mind that 

 the tree is one which requires an immense space, should rearing from 

 seed be resorted to, which however, can scarcely be necessary ; it must 

 be remembered also, that the most favorable situation for ensuring their 

 vegetation would appear to be on other trees, and they should be so 

 placed as not to be liable to be removed either by rain or wind. Some 

 manure should be placed with them so as to imitate as much as possible 

 that with which they are generally supplied by birds. 



The substance, caoutchouc, is a widely disseminated constituent of 

 vegetable fluids. It has hitherto, I believe, been found only in plants 

 with milky juice, although its presence in all plants yielding such fluid 

 remains to be proved. The presence of caoutchouc in silk has been, 

 I believe, attributed to the nature of the fluids of the plants on which 

 the caterpillars feed : but this, although applicable to the mulberry 

 plants, can scarcely hold good with the various species of Tetranthera on 

 which the Moonga feeds, or with the castor-oil plant the chief food of 

 the Eria, which in Assam does not appear to yield milk. Milky juice is 

 often characteristic of certain families, but often not : its presence is fre- 

 quently of importance, as it often affords valuable indications of affinity. 

 It is remarkable that it is almost unknown in the grand division of 

 Monocotyledonous plants. The families in which its presence may be 

 said to be universal are Apocquea, Asclepiadea, Campanulacea, Sobelia- 

 cea, and the great division of Composite, Chichoracea, of which the let- 

 tuce is a familiar example. It is of common occurrence in Euphorbiacea, 

 and Tulicea, which orders may be looked on as the grand sources of 

 caoutchouc. Thus, in addition to our Indian plants, the American caout- 

 chouc is supposed to be produced by Cecropia peltata which belongs to 

 Urticea, and the Ule tree of Papantla, from which the caoutchouc of that 

 country is obtained, is supposed to belong to the same orders. I must, 

 however, observe that Baron Humboldt objects to the supposition of 



* For this information I am indebted to Captain Jenkins. 



