Of the sixteen genera enumerated by Dr. Seemann, and given in the table below, only about half now retain their character of being restricted to Fiji. Nor does it seem likely that future investigations will increase this number, since, judging from a remark made by Mr. Hemsley in his paper on the botany of the Tongan Group, explorations subsequent to those of Dr. Seemann, more especially those of Mr. Horne, have not apparently added a single new endemic genus to the Fijian flora. It will be seen from the list that at least four of the sixteen genera have since been found in the Malayan region, and in one case (Smythea pacifica) the same species occurs in both regions; whilst a fifth genus (Haplopetalon) has been recorded from New Caledonia.
There are, however, some peculiarities about the Fijian endemic genera that will attract our attention from the standpoint of dispersal. One remarkable feature is the paucity of species. Almost all the genera are monotypic, that is to say, they are only known by a single species. Amongst the twenty-eight Hawaiian genera that are strictly endemic, only four or five are monotypic, and they are mostly regarded by Hillebrand as worn-out, decadent types found in only one or two islands. In Hawaii there are on the average six species to each endemic genus; and it is thus apparent that in the display of formative energy Nature has worked on very different lines in these two groups. Since the nine Fijian endemic genera belong to nearly as many different orders, the composition of this endemic generic flora is by no means homogeneous. It is, I venture to think, such a motley collection as one might expect in a region that has been exposed to wave after wave of migration from the west, with no lofty mountains, as in Hawaii, to afford a refuge against extinction. It by no means follows that all these endemic genera have been produced in Fiji. Some of them may represent genera that have become extinct in the large continental groups to the westward.
SEEMANN’S SIXTEEN FIJIAN ENDEMIC GENERA.
| Genus. | Order. | Number of species. | Character. | Fruit. | Affinities or other localities. |
|---|---|---|---|---|---|
| Richella | Anonaceæ. | 1 | Tree. | Baccate(?). | Indian in type (C). |
| Trimenia | Ternstrœmiaceæ. | 1 | Tree. | Unknown. | |
| Pimia | Sterculiaceæ. | 1 | Tree. | Small spinose capsule. | Related to Australian genera (S). |
| Græffea | Tiliaceæ. | 1 | Tree. | Unknown. | Near Trichospermum, a Fijian and Malayan genus (S). |
| Thacombauia | Humiriaceæ. | 1 | Shrub. | Drupe. | Order mainly South American. |
| Amarouria | Simarubeæ. | 1 | Tree. | Dry drupe. | Near Soulamea, a Malayan genus (S). |
| *Smythea | Rhamneæ. | 1 | Straggling shrub. | Capsule. | Also in Burma, New Guinea, and Malaya (IK), (Sc). |
| *Oncocarpus | Anacardiaceæ. | 2(H) | Tree. | Drupe. | Also in New Guinea (IK). |
| *Haplopetalon | Rhizophoreæ. | 2 | Shrub. | Unknown. | Also in New Caledonia (IK). |
| *Nesopanax | Plerandreæ. | 1 | Tree. | Drupe. | =Plerandra (IK). |
| Bakeria | Plerandreæ. | 1 | Tree. | Drupe. | |
| Pelagodendron | Rubiaceæ. | 1 | Shrub. | Berry. | |
| *Paphia | Ericaceæ. | 1 | Shrub. | Berry. | =Agapetes, a Malayan genus (IK). |
| *Carruthersia | Apocyneæ. | 2(H) | Climber. | Berry. | Also in Philippines (IK). |
| *Couthovia | Loganiaceæ. | 2 | Tree. | Drupe. | Also in Kaiser Wilhelmsland, New Guinea (So). |
| Canthiopsis | Loganiaceæ. | 1 | Shrub. | Drupe. |
Those genera marked * have since been found outside the group.
The authorities are thus indicated: (C)=Drake del Castillo; (H)=Horne; (IK)=Index Kewensis (S)=Seemann; (Sc)=Schimper; (So)=Solereder in Engler’s Nat. Pflanz. Fam.
The fact that several of them are fitted for dispersal by frugivorous birds is very suggestive of the lack of means of transport in later times. In the instance of Couthovia corynocarpa the drupes are known to be the food of fruit-pigeons at the present time (Seemann), whilst this is also true of Oncocarpus vitiensis, though this genus has since been found in New Guinea. Since, as will be pointed out in a later chapter, birds must still be fairly active in carrying seeds to Fiji from regions westward, it would seem that genera only become peculiar to Fiji when they fail at their source, and it is indeed doubtful whether any of the Fijian peculiar genera are home productions. One may instance in this connection the genus Pimia, the fruits of which are especially well suited for attachment to a bird’s plumage, yet it is only known from Fiji.
It should be here observed that no peculiar generic types have been recorded from the adjacent Tongan Group, and scarcely any from Samoa. Except perhaps with the Palmaceæ, no peculiar genera seem to be mentioned in Dr. Reinecke’s memoir on Samoa.
Summary.
(1) The Lobeliaceæ, like the Compositæ, take a prominent place in the early Pacific flora, being represented, more particularly in Hawaii but also in the East Polynesian or Tahitian region, by endemic genera of tall shrubby and tree-like species.