CHAPTER XX 



THE EPOCHS IN THE FLORAL HISTORY OF THE PACIFIC 



ISLANDS 



THE AGE OF FERNS 



The epochs in the plant-stocking. The age of ferns and lycopods. The 

 relative proportion of vascular cryptogams in Hawaii, Fiji, and Tahiti. 

 The large number of peculiar species in Hawaii. The mountain ferns of 

 Hawaii. The origin of peculiar species. Dr. Hillebrand's views. Their 

 origin connected not with greater variety of climate in Hawaii, but with 

 isolation. Summary. 



Introductory Remarks 



IN the endeavour to follow the various stages in the floral history 

 of the Pacific islands from the standpoint of plant-dispersal, a 

 method is here adopted which is not often employed. The usual 

 mode of making a general description of a flora is not intended to 

 bring out its genesis in point of time. We describe the result of a 

 long series of changes dating back to some unknown period, much 

 as one might describe the present condition of a people without 

 reference to their history ; and for obvious reasons rarely is an 

 effort made to differentiate the epochs of the stocking of the 

 region with its plants. The difficulties investing such a task in the 

 case of a region situated within a continental area would be almost 

 insuperable. With the oceanic groups of the Pacific such diffi- 

 culties, though still very numerous, would at all events be fewer in 

 number and less formidable in appearance. 



Taking my cue from the well-known instance of Krakatoa, it 

 is here assumed that the earliest epoch is connected with the 

 arrival of the cryptogamic flora (ferns, mosses, lichens, &c.) through 

 the agency of the winds, and with the arrival of the littoral plants 



