jDCTOBER, 1908.] 



317 



Saps and Exudations* 



According to the above, we must use 

 for the extraction of the milk from 

 the roots, cups of raw clay, which 

 although they improve the product, still 

 are liable to crack and allow part of 

 the milk to escape, and deposit itself 

 in the soil. 



For the use of extraction by the 

 roots, the best cups or basins should be 

 those of clay baked and glazed inside, 

 which stops the filtering through of 

 the water or solution employed. They 

 should affect the form of a semi-cir- 

 cumference, ten centimetres in diameter 

 (4 inches) offering the greatest surface 

 at the part whicb has to remain 

 adherent to the root to permit of several 

 cuts being made. To where the cups 

 or basins adhere perfectly to the root, 

 it is necessary at the point of junc- 

 tion to place clay plaster to fasten the 

 cups to that part. 



The cups can be made of zinc sheet. 

 A cow's horn can also be used. The 

 cups for the extraction from the branches 

 should be as deep as a glass. 



We will now treat of a part no less 

 important. — knowing the mean produc- 

 tion from a tree in a Avild state, and 

 advantages of culture of Manieoba. 



Mean Production of Rubber per 

 Tree. 



Collecting carefully and separately the 

 production obtained from fourteen trees 

 was found to give the mean of 57 "73 

 grains per plant. 



Afterwards taking another production 

 of ten trees the mean was 77"15 grains 

 per plant. 



We found one tree Avhose production 

 taken by itself attained 197 - 50 grains. 



According to these results obtained 

 under the irregular conditions of the 

 dry and bad season, it is seen that the 

 mean is not disappointing ; it should also 

 be notice d that those trees submitted for 

 the test, in the majority had already 

 suffered from previous tappings. 



Production of a Tree in its Wild 

 State under Normal Conditions. 

 Takiug into consideration the dry and 

 bad seasons and the losses in the extrac- 

 tion, it may be safely estimated at 100 

 grains the mean of production of one 

 tree in its wild state, during the time it 

 is undergoing tapping. 



* * * -a * * * 



The Manicoba as Producer of 

 Forage. 



The seeds constitute a food, liked by 

 cattle, and of great alimentary power 

 from the richness of fat materials, and 



can be ground to produce a rich forage, 

 superior perhaps to the flour of the seeds 

 of cotton and other similar seeds. 



The Time which passes from Culture 

 to Perfection. 

 It appears to us that the Manicoba has 

 a rapid growth, principally at the com- 

 mencement of the development ; we 

 believe that from the 4th to the 5th year 

 it can produce, but the maximum of 

 production is during the 8th year for- 

 ward, as with the cocoa and other plants. 

 * * * * * * 



Augmentation of the Production of 

 Rubber in Manicoba during the 



Extraction of the Milk. 

 Manicoba is educated in its production 

 of rubber or of milk, in the same manner 

 as the breasts of animals are habituated 

 to give the maximum production of milk ; 

 during our labours we observed the 

 augmenting in the production of milk, 

 after repeated taps, the fact is known to 

 all the extractors of rubber from Mani- 

 coba.— Bulletin of the Department of 

 Agriculture, Jamaica, Vol. VI., Pts. 2 & 

 3, Febuary and March, 1908. 



REMARKS ON THE CULTIVATION, 

 PREPARATION AND YIELD 

 OF MANICOBAS. 



By Aug. Cardozo. 

 (Abstracted by R. H. Lock.) 



The author uses the term Manicoba to 

 include Ceara rubber, and it is with this 

 product that the paper chiefly deals, only 

 a brief reference being made near the end 

 to the true Manicoba varieties in the sense 

 in which that term has hitherto been 

 used in the T. A. and Mag. of C.A-S. 



Reasons are given for the comparative 

 failure of Ceara rubber as an agricultural 

 crop. The chief of these are :— 



(1) The lack of a satisfactory method 



of extracting the latex. 



(2) The large proportion of badly 



yielding trees which are often 

 found in plantations. 



It is stated that only 15 or 20 % of the 

 seeds of any variety will yield good trees, 

 so far as yield of rubber is concerned. 



It is impossible to tell which seeds will 

 yield good trees before they are sown, but 

 a choice may be made of these seedlings 

 which grow most rapidly, with a large 

 main axis, and produce a thick latex, 

 oqaque and not sticky. 



In order that the latex may be readily 

 extracted, the trunk must be verticle, and 

 branching must not begin too close to 

 the ground. 



