XVII.—Keys to the Perns of Borneo 
By Edwin Bingham Copeland, Dean and 
Professor of Plant Physiology, College of 
Agriculture, University of the Philippines. 
INTRODUCTION. 
In the extent to which its ferns, as well as its other 
native plants, have been collected and studied, Borneo 
has remained very far behind Java, on the south, and the 
Philippines, on the north-east; Sumatra, to the west, and 
Celebes to the south-east have likewise remained behind, 
perhaps even further than Borneo. There is no reason¬ 
able doubt that Borneo has the largest fern flora of any 
of the Malayan islands. And, with the improbable 
exception of New Guinea, its fern flora, when well 
investigated, may be expected to prove the richest in the 
world. In spite of the years of collecting by such keen 
friends of the ferns as Bishop Hose and Mr. Brooks, it 
remains the case to-day that a few very small localities in 
Western Sarawak and one trail up to Mt. Kinabalu are 
the only places in Borneo, which can be considered 
scenes of reasonably thorough reconnaissance collecting. 
Judging from experience in the Philippines, it may well 
be supposed that 40 per cent, of the species of Bornean 
ferns still remain to be discovered ; and that of endemic 
species, we are acquainted at the present time with 
decidedly less than half. 
A 
