6. _Ficus platyphylla_.—“Red Kano rubber,” or “Ballata,” known to the Nupe people as “Ogbagba.” This is prepared by boiling, without the addition of any foreign matter, and attains the consistency of a hardened paste, similar to the “guttas” made from the latex of the Shea-butter tree (_Butyrospermum Parkii_). It is distinguished in the Kano Province by the name “Danko Gawi,” shea gutta being known as “Danko Kadainya.” 7. _Ficus trachyphylla_.—This tree is called in Ilorin by the Yoruba name “Oapottoa,” and yields a latex which is discoloured pink by the sap of the tree with which it becomes mixed in tapping. When boiled and allowed to cool, the product is a reddish hardened substance, somewhat resembling guttapercha in appearance. 8. _Ficus Vogelii_.—Scrap rubber from this tree is said to be collected. In appearance this rubber is often good, but the shreds break up easily. It will be seen from the above, that several of the so-called rubbers are unlike the valuable kinds in appearance and composition, and as such are, perhaps, incapable of being used in a pure state and for the most important manufactures for which rubber is employed. All kinds, however, seem to be marketable at a price which is remunerative to the exporter, so that the trade has become an extensive one. =Plantations.=—It has been urged that Para rubber (_Hevea brasiliensis_) might be grown upon a large scale in the moist and well-watered areas, and Ceara (_Manihot Glaziovii_) and _Funtumia elastica_ in the drier districts; but the country is not generally favourably adapted for growing the first and last mentioned. Ceara rubber seems to thrive well in climates similar to that of this country, and the rubber made from it is of the finest quality, but in many tropical countries it has shown great uncertainty in yield of latex, and often unaccountable cessation of flow. This has caused it to be less favourably regarded for plantation work. (Cf. _Bull. Imp. Inst._, 1913, 1916.) Many parts of the country are suitable for Ceara cultivation, thriving as it does in localities susceptible to long periods of drought. In the German African Colonies the method of treating the tree seems advantageous, in view of the uncertainty of the yield after maturity is reached. In these places the plants are put out in extensive plots each year, and, after they have reached full growth, all the latex possible of extraction is taken out of them, and the exhausted trees are cut out, permitting the area to become renovated by the self-sown seedlings, which spring up in great profusion. Thus, each year a plot becomes completely renovated, without great expense being incurred. If Ceara planting should be adopted in Northern Nigeria, some such system as this might prove remunerative.