Gums, Resins 



396 



[May, 1910. 



is far less. One of the advantages, a 

 subsidiary advantage, to accrue from 

 cultivation is that of systematic control 

 of the cropping by a special staff of 

 workers, for the itinerant collectors of 

 wild rubber cannot always be counted 

 upon. 



I detected in the Manicoba forests 

 several distinct varieties of this tree, 

 and on enquiry I found that one parti- 

 cular variety was recognised as being 

 richer in latex than others. The 

 varieties are distinguished by colour, 

 size,' and lobe formation of the foliage, 

 which latter are remarkably vigorous in 

 cultivated plants. The uncultivated 

 trees are sparsely furnished with foliage. 

 I have had considerable experience with 

 regard to the effects of soil on rubber 

 plants- Apart from the large planta- 

 tion of Virgen rubber which I established 

 in Columbia, I planted experimentally 

 more than quarter of a century ago, 

 both in Jamaica and in Columbia many 

 plants of Ceara, a nearly related species 

 ot Manicoba. Furthermore, I intro- 

 duced to Jamaica many plants of Para 

 rubber, Castilloa and Virgen rubbers. 

 Unfortunately, until recently, no atten- 

 tion has been paid to their propagation 

 in that colony. 



The Hevea (Para rubber) is indigenous 

 to another part of Brazil. In addition 

 to the boundless tracts of country 

 throughout which it is dispersed, it is a 

 large tree. It furnishes in a wild state 

 most of the rubber found in commerce. 

 But the natural resources of the forest 

 gradually dwindle. This is the tree for 

 cultural purposes that has claimed the 

 attention of the capable planters of the 

 East with far-reaching consequences. 

 The species flourishes in conditions of 

 soil and climate the converse of those 

 requisite for the humble Manicoba tree. 

 Hence, the latter species can never be 

 cultivated side by side with its great 

 Amazonian rival. 



Supplementary to my foregoing ac- 

 count of this species of rubber, I think 

 it is important to cite from, and append 

 hereunto, an interesting article in the 

 Kew Bulletin, No, 2, 1908, on this subject, 

 which, inter alia, contains much infor- 

 mation supplied by Mr. O'Sullivan Beare, 

 H. B. M's Consul at Bahia, to whom I 

 had a letter of introduction from the 

 Governor of Jamaica. 



In the year 1906, Dr. Ule, a German 

 Botanist, who visited Bahia, named the 

 Jequie Manicoba, Manihot dichotoma. 



" The Jequie Manicoba is undoubtedly 

 a new and distinct species of Manihot, 

 and it must not be confounded with the 

 Manihot of Ceara, Manihot Glaziovii. 



This discovery is a matter of much 

 importance, not only to this State, but 

 also for the rubber trade in general, in- 

 asmuch as the rubber obtainable from 

 the Jequie Manicoba when properly 

 prepared would seem to be equal in 

 quality to the best product of the Para 

 region. 



"The season for extracting the latex 

 from the Jequie Manicoba extends from 

 August to March. The latex possesses 

 the valuable property of coagulating 

 spontaneously when exposed to the air, 

 and it requires no acid or artificial 

 coagulant of any kind." 



"A planter, established in the Jequie 

 district, recently prepared a consider- 

 able quantity of rubber obtained from 

 Manicoba trees growing wild in that 

 neighbourhood, and despatched it to 

 New York. The consignment was classi- 

 fied in the New York market as being 

 equal to the best Para rubber, and it 

 fetched one dollar twenty cents (5s.) 

 per lb." 



In addition to Manihot dichotoma, 

 two distinct and nearly related rubber- 

 yielding species were found by Dr. Ule, 

 " the one growing on the mountains of 

 the right bank of the Rio San Francisco, 

 and the other, confined to the country 

 at some distance from the left bank, 

 occurring especially in the adjoining 

 State of Piauhy." . . . These two 

 species are described under the name 

 M. heptaphylla and M. piauhyensis. 



My examination of this species of 

 rubber, Manihot dichotoma, in its native 

 habitat, set forth in my preceding ac- 

 count, shows that I am impressed with 

 the remarkable possibilities of this rub- 

 ber-yielding plant, thus having arrived 

 at the conclusion that, under cultiva- 

 tion, it is destined to rank in productive- 

 ness, per acre, second to none. It there- 

 fore seems obvious that some confusion 

 has arisen in the publication of a para- 

 graph in the Kew Bulletin, wherein 

 this species as regards its rubber-yield- 

 ing capacities is undoubtedly misrepre- 

 sented. A comparison is made with 

 this and the two other allied species, 

 namely, M. heptaphylla and M, piau- 

 hyensis. In this comparison it is stated 

 that the yield of rubber per tree under 

 cultivation for the two latter actually 

 exceeds the yield for M. dichotoma five- 

 fold ? Thus, " the yield of rubber from 

 a single tree of it, dichotoma in one 

 year can be reckoned at from 100-200 

 grammes." And, the annual yield of 

 rubber for single trees of M. piau- 

 hyensis is from 500-1000 grammes." Said 

 paragraph is here subjoined. 



