18 



Momi Inundation Area. 



From the forest one emerges into the blazing sunshine, on an open plain, 

 which it takes several hours to cross, all stones, gravel, sand, and " lalang," 

 dotted with small trees of Casuarina equisetifolia. This open space forms an 

 inundation-area of the river, and is under water during the rains. Amongst 

 the stones Geodorum pictum, a pink-flowered orchid, was characteristic, and 

 Peristylus goodyeroides was found among the " lalang " which covered the 

 sandy areas. The most remarkable feature was abundant clumps of a new 

 Pteris, P. bamliisoides, with erect rhachises resembling stems rising from an 

 underground rhizome, each rhachis about 2 m. in height, clothed \vith 

 segments from the base to the apex, originally bilateral, becoming spiral 

 later through the twisting of the cortex. The species was also seen near 

 Wariap, in passing through the " kebuns." Professor Bower, to whom 

 I submitted this interesting new fern, suggests that " the general habit 

 might possibly compare with that of Pteris grandiflora, in so far that both 

 are probably creeping rhizomatous." 



Pandanus Trees. 



The second day, while still in the " korang " forest, we passed through a 

 striking group of old Pandanus trees, about 30 in. high, each rising out of 

 the forest on numberless grotesque stilt roots for about a quarter of the 

 height, succeeded by a straight stem with much-branched top ; the old 

 leaves hung in limp masses from every possible resting-place and strewed 

 the wet ground underneath. These weird trees gave a pregnant impression 

 of the scenic possibilities of this genus under primitive conditions. Even 

 the Malays were impressed ; but the Papuans spoke of similar isolated 

 groups scattered through this forest. These groups possibly represent 

 the first vegetative covering of the " korang/' displaced later by more 

 rapidly growing dicotyledonous forest trees, as only those plants which 

 could respond by equal vertical growth and so maintain the same level 

 as their competitors would have a chance of survival under such enveloping 

 conditions. No fruit was seen on the trees or underneath them. 



(c) SECONDARY ASSOCIATIONS. 



Once on the foot-hills the character of the forest changes, the sodden 

 effect of the "korang'* belt works out, and it loses the mud-washed look 

 and steaminess suggestive of constant inundation. The ground, rocky and 

 broken, is strewn with Sapindaceous and Anacardiaceous fruits, red Pometia, 

 and other brightly-coloured kinds, and undergrowth in the shape of plants 

 and shrubs appears, Musscenda frondosa being general. The foliage of both 

 trees and lianes is less monstrous and more varied in form, while a graceful 

 epiphytic flora puts in an appearance. From time to time small cleared 



