48 



So much is this the case that the history and country of origin of immigrant 

 man, to whose agency the presence of this " Opportunity flora " is indirectly 

 due, can be pretty accurately determined by the nature of the invading plants. 

 It is the absence of aliens in the " Opportunity " associations of the Arfak 

 which form the engrossingly interesting feature in the phytogeography 

 of this region. 



1. Open Marsh. 



Endemism is the dominant note in the plant-covering of this marsh. 

 Most of the dominant plants found there are now described for the first time, 

 or were first collected by Beccari and Gjellerup. One or two have been 

 previously described from New Guinea, as Erwcaulon leucoyenes and Trisetum 

 latifolium ; others, to quote new Papuan records alone, are incidental wind 

 immigrants from the Himalayas, as Xyris pauciflora, Polygonum strigosum, 

 and Viola distans. The latter is unknown in Malaya with the exception of 

 the Philippines, while the others reach N.E. Australia, and therefore their 

 incidence in New Guinea was to be taken for granted. In Utricularia 

 racemosa and 7. bifida, the former shows the Himalayan range and the 

 latter is limited to Malaya, while Gahnia psittacorum, abundant on both 

 these open areas and also at home in the forest, reaches E. Australia and 

 Tasmania. Most of the other Cyperacese are cosmopolitan tempei-ate types, 

 of incidental wind distribution, like the cryptogams, of which, in relation to 

 the freshwater Alga?, Professor West writes " that all the species observed 

 are ubiquitous, few of the tropical ascending to 7000', the one exception 

 being Closterium Bacillum, known only from Burma." The lichens, most 

 mosses and ferns, including the Lycopodiums of these areas, are also cosmo- 

 politan, while the only Selaginella collected is endemic. 



The one plant to suggest man's agency was J)esmodium Scalpe, an 

 unexpected representative of a genus that, may almost be described as alien 

 to the Papuan mountain flora, but, growing on the site of van Oosterzee's 

 and the Pratts' camps, it may be considered the one relic of alien intrusion. 

 On Kinabalu this plant has so far only been found at Lobang, on the 

 invariable camping-site. 



2. Cladonia A ssociation of Koelre. 



Nonb of the ombrophobous herbaceous plants with the exception of the 

 Riedelias, a feature of the open spaces of the S.W. ridge and of this summit 

 plateau, were collected in the surrounding forest. They were all plants 

 requiring constant illumination and low temperature for their development, 

 of which the germination of the seeds would be inhibited under shade 

 conditions. 



Some of these plants, such as the Dendroliums and Centrolepis, are 

 common to the open spaces of the S.W. ridge and to the marsh ; of the 



