XXIV THE FIJIAN CONIFER^E 303 



The three Fijian genera of the Coniferae, Dammara, Podocarpus, 

 and Dacrydium, appear at first sight to be beyond the reach of our 

 canons of plant-dispersal, by which we connect specific affinity 

 with a continuity of range, and by which we co-ordinate means of 

 dispersal and area of distribution. We begin to realise that there 

 may have been an age of Coniferae in the Pacific islands that 

 is even less amenable to our methods than the later era of the 

 Compositae and Lobeliaceae in Hawaii and Tahiti. Such an age 

 would be concerned only with that region in the Western Pacific 

 which is now held by the genera Dammara, Podocarpus, and 

 Dacrydium, a region that did not participate in the era of the 

 Compositae and Lobeliaceae. We thus have evidence of an ancient 

 era of the Coniferae that was confined to the Western Pacific, and 

 of a later era indicated by the peculiar genera of Compositae and 

 Lobeliace^ that was restricted to Hawaii and to Eastern Polynesia 

 (Tahiti, Rarotonga, &c.). The key to the situation here presented 

 seems to lie in the following considerations. 



It is assumed that there was an age of Conifers in the Pacific, 

 or rather that this region shared in an era of dispersion of existing 

 genera of the order. In this age only the islands of the Western 

 Pacific participated, neither the Hawaiian nor the Tahitian islands 

 taking a part in it. Such a result is to be attributed either to the 

 inability of these genera of Conifers to reach Hawaii and the 

 islands of East Polynesia, or to the non-existence of the Hawaiian 

 and Tahitian archipelagoes at that epoch. The first explanation 

 seems scarcely acceptable, since, although the powers of dispersal 

 of the genus Dammara are very limited, there seems no reason 

 why the genera Podocarpus and Dacrydium could not have 

 reached those distant regions of the Pacific. The second explana- 

 tion is most probable, and it is the one suggested by Hillebrand 

 (p. xxx) in the case of Hawaii, namely, that " the absence 

 of Gymnosperms militates for the view that the islands were 

 formed subsequent to the age in which these were universally 

 distributed." 



If this conclusion is legitimate we have here a datum-mark in 

 the history of the islands of this ocean. Before the appearance of 

 the Hawaiian and Tahitian islands (using the term Tahitian to 

 cover the East Polynesian region) there existed a land-area in 

 the Western Pacific held by the Conifers, probably in the late 

 Secondary period. After the formation of the Hawaiian and 

 Tahitian islands, perhaps in the early Tertiary epoch, came the 

 age characterised by the ancestors of the present endemic genera 



