* 3 8 
Forest Flora of Portuguese East Africa. 
If ever cultivation of this species is attempted in this Province, I would recommend the higher and moister districts rather than the flats. My observation would lead 
me to think stagnant water more fatal than drought, but I think the flow of latex will be found to correspond with the supply of running water available. The presence of this 
probably reduces the value of Quelimane rubber meantime. Johnson considers the latex of Landolphia Buchanani (or a closely allied form) equal to that of L. kirkn , and 
finds that L. florida in his district yields what may be a marketable though low-grade commodity. 
He also thinks it possible that a local Ficus, which he calls F. Vogelii, miq., may yield a Caoutchouc worth exploiting, as samples prepared by him from the same 
species on the west coast were valued by London brokers at 2/- per lb. Every Ficus yields latex, more or less, but I presume he refers to what 1 have described as F. utilis, of 
which I sent Gutta-percha to London from Natal Maputa in 1904, under the name Mpai, and was favoured by the Director of the Imperial Institute with the following report 
“ The sample of ' Mpai ’ rubber submitted for examination consisted of a flat elongated cake, which weighed about 35 grains. It was light-brown externally, but the freshly-cut 
surface was less coloured and showed a pinkish tinge. The material could be easily indented with the finger-nail, and exhibited very little elasticity but considerable tenacity ; 
it had a somewhat fibrous structure, resembling that of gutta-percha. When placed in warm water it softened a little without becoming sticky, and could then be readily drawn 
out to a considerable length, but the elasticity was only very slight. The physical properties of the material seem to be intermediate between those of true rubber and gutta- 
percha, a common feature of the products yielded by species of Ficus, but in composition, as shown by the analysis shown below, it is much more closely related to rubber. 
The chemical examination furnished the following results : — 
Sample as Received. 
Calculated for 
Dry Material. 
l’ER CENT. 
PER CENT. 
Moisture 
28'4 
— 
Resin - 
499 
6 g '6 
Caoutchouc - 
1 9'6 
27-4 
Dirt - 
2 ' I 
3 ° 
Ash, included in dirt - 
0-79 
no 
The material, therefore, consists principally of resinous substances, which form 69 6 per cent, of the dry material, whilst only 27-4 per cent, of true caoutchouc is present. The 
isolated caoutchouc was not very strong, but was quite free from stickiness. The sample was submitted for commercial valuation to brokers, who were informed of its chemical 
composition and properties. They report that the material would be suitable for certain technical purposes and that sales could probably be effected at about io£d. or nd. 
per lb." 
Forester Gryspert, of Maputa, who prepared this sample, wrote as follows : — “The Mpai grows both near water and also to perfection in dry sandy bush. Mpai will 
give, in my opinion, a gutta-percha, if not of the very best quality, of such quality as will make it pay better than Landolphia. This sample shows that the latex of Mpai can be 
worked with freedom from stickiness in its natural state, without either boiling, water, heat, smoking, or chemicals ; the sample enclosed is pure unadulterated latex of Mpai, 
worked by hand after 48 hours’ rest. Latex of Mpai contains very little water, practically none, consequently there is no loss. Of Mpai trees I would certainly put 300 or 400 
on the acre, and the weight of gutta per acre would be about double that of Para, or any other rubber. I can now collect in one day one quart of latex of Mpai. This quantity 
should be increased in plantations." 
This Ficus grows in abundance throughout the Province and is easily struck by large cuttings ; it is the same tree from the liber of which the M’Chopes natives manu- 
facture their native cloth, and it is used for cordage wherever it occurs. While I do not share Forester Gryspert’s optimism as to its utilisation being more profitable than that of 
Landolphia I still think, considering its enormous flow and easy culture, that there is money in it, especially on light sandy soils, and near running water. There are various 
Apocynaccous trees and shrubs besides Mascarenhasia which may be worth attention in this respect, particularly Voacanga Thouarsii and Conopharyngia ventricosa and C. 
elegans. All these bleed on being tapped, but most profusely from the large fruits, and as the latter species is found in great abundance in the extra-tropical districts, and with 
a little encouragement would be much more so, and fruits abundantly, I think it probable that a large industry may yet be established in the collection and tapping of these fruits, 
in which every woman and child could take part. The latex is used by the natives as bird-lime ; and I am not aware that it has ever been analyzed, but the simple cultivation, 
the easy collection, and profuse flow- of latex all indicate that further attention may be repaid. 
Diplorhynchus mossambicensis also bleeds freely, especially from the fruit, but as this occurs only in the tropical districts, where Landolphia is not yet fully utilised, I 
think its time has not yet come. 
An Kuphorbiaceous tree of rapid growth and large size found by me on the south side of the Inharreme River only, but said to grow through Zuvalla, of which 
specimens obtainable were insufficient for identification, yields a most abundant flow of rather thin latex, more abundant indeed than any other of our trees, but as it did not 
