APPENDIX 



of Cryptocoryne pallidinervia, Engl., which lives in stagnant waters in the 

 forest, and is the only known aquatic plant with variegated leaves. 



Saprophytes. — There can be no doubt that the plants of the Bornean 

 forest have been perpetually engaged in a struggle against numerous 

 enemies, who have ceaselessly striven to destroy or to damage not only 

 their aerial parts, but also those which lie beneath the soil. At the 

 present time, as in the far remote past, the struggle for existence in plants, 

 even beneath the surface, against micro-organisms and the mycelia of 

 a host of fungi must have been incessant. The final result can only 

 have been the extinction of all those vegetable forms which did not 

 possess a sufficient power of resistance, or which were unable to adapt 

 themselves to their surroundings, modifying themselves so as to be 

 victors in the battle. In the latter condition were probably many of 

 the forest ground plants, which might almost be said to have come to 

 an agreement with their foes, conceding to them a hospitality which 

 appears ultimately to have proved of service to them, for the outcome 

 of the struggle is a condition of mutualism advantageous to both parties. 

 The presence of mycorhizse in the roots of plants may have had such 

 an origin. 



Humicular saprophytal plants are frequent in Borneo ; it is sufficient 

 here to mention the genera Burmannia, Thismia, Geomitra, Triuris, 

 Salomonia, Petrosavia, and some orchids (Lecanorchis, Aphyllorchis, etc.). 



Parasites. — True parasitic plants in Borneo may be divided into 

 two classes, viz.. the aerial, and those which may be termed terrestrial, 

 since it is on the roots of plants that they have established themselves. 



Except the well-known and wide-spread Cassytha, a type of the 

 common Cuscuta, the aerial parasites in Borneo all belong to the family 

 of the Loranthacece, and, with the exception of some species of Viscum, 

 all to the genus Loranthns, largely represented by conspicuous species 

 with brightly coloured flowers, in which red and yellow predominate, 

 and bearing large bracts almost equally resplendent. The Loranthacece 

 are true parasites, preferring to attach themselves to the higher branches 

 of trees, where their flowers are more exposed. In Borneo, however, 

 I also found a terrestrial Loranthus, Macrosolen Beccarii, Van Tiegh 

 (P. B., No. 610), a humble forest shrub, which is apparently non-parasitic. 

 I have been able to ascertain positively that the " burong unparu " 

 (Trachycomus ochrocephalus) feeds on the fruits of Loranthus ; but 

 probably many other birds feed on them also. It is also probable that 

 some slender-billed birds, and perhaps some butterflies, are attracted 

 by the brilliancy of the flowers of plants of this genus, and that they take 

 part in their fecundation, but- 1 have no personal observations on this 

 subject. Nearly all the Loranthacece have thick fleshy leaves, or else 

 are clothed with woolly down ; the above-mentioned Macrosolen Beccarii 

 alone has glossy and thinly coriaceous leaves. They are the despair of 

 botanists who have to prepare specimens for the herbarium, for whatever 

 precautions are taken they break up during the process of drying. 



The species of terrestrial parasites known to me from Borneo are 

 only two species of Balanophora, the Brugmansia Lowii and Rafflesia 

 Tuan Mtidce, Becc. 



The genus Rafflesia only contains a restricted number of species, 



388 



