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Show 306 ISLAND LIFE. [l'AR'L' II. Horace Mann, and of Dr. Pickering, who accompanied the United States Exploring Expedition. Considering their extreme isolation, their uniform volcanic soil, and the large proportion of the chief island which consists of barren lava-fields, the flora, of the Sandwich Islands is extremely rich, consisting, so far as at present known, of 554 species of flowering plants and 135 ferns. This is considerably richer than the Azores (439 Phanerogams and 39 ferns), which thou()'h less extensive are far better known, or than the Gala- o pagos (332 Phanerogams), which are more strictly comparable, being equally volcanic, while their somewhat smaller area may perhaps be compensated by their proximity to the American continent. Even New Zealand with more than twenty times the area of the Sandwich group, whose soil a.nd climate are much more varied, and whose botany has been thoroughly explored, has not double the number of flowering plants (935 species), while in ferns it is barely equal. Peculia1· Features of the Fl01·a.-This rich insular flora is wonderfully peculiar, for if we deduct sixty-nine species, which are believed to have been introduced by man, there remain 620 species of which 377, or more than three-fifths, are quite peculiar to the islands. There are no less than 39 peculiar genera out of a total of 253, and these 39 genera comprise 153 species, so that the most isolated forms are those which most abound and thus give a special character to the flora. Besides these peculiar types, several genera of wide range are here represented by highly peculiar species. Such are Lobelia, the Hawaiian species of which are woody shrubs from six to twenty feet high, one even being a tree, reaching a height of forty feet. Shrubby geraniums fifteen feet high grow as epiphytes on forest trees, as do some Vacciniums and Epacrids. Violets, and plantains also form tall shrubby plants, and there a.re many strange arborescent compositre, as in other oceanic islands. The affinities of the flora genemlly are very wide. Although there are many Polynesian groups, yet Australian, New Zealand, and American forms are equally represented. Dr. Pickering notes the total absence of a large number of families found in Southern Polynesia, such as Dilleniacere, Anonacere, Olacacere, CHAP. XV.] 'l'IIE SANDWICH ISLANDS. 307 Aurantiacere, Guttiferre, Malpighiacere, Meliacere, Combretaccre, Rhizophoracere, Melastomacere, Passifloracere, Cunoniacere, J asminacere, Acanthacere, Myristicacere, Casuaracere, Scitaminere, and Aracre, as well as the genera Clerodendrum, Ficus, and epidendric orchids. Australian affinities are shown by the genera Exocarpus, Cyathodes, Melicope, Pittosporum, and by a phyllodinous Acacia. New Zealand is represented by Ascarina, Coprosma, Acrena, and several Cyperacere; while America is represented by the genera Nama, Gunnera, Phyllostegia, Sisyrinchium, and by a red-flowered Rubus and a yellow-flowered Sanicula allied to Oregon species. There is no true alpine flora on the higher- summits, but several of the temperate forms extend to a great elevation. Thus Mr. Pickering records V accinium, Ranunculus, Silene, Gnaphalium and Geranium, as occurring above ten thousand feet elevation; while Viola, Drosera, Acama, Lobelia, Edwardsl.a, Dodonrea, Lycopodium, and many Compositre, mnge above six thousand feet. V accinium and Silene are very interesting, as they are peculiar to the North Temperate zone, except one Silone in South Africa. The proportionate abundance of the different families in this interesting flora is as follows:- 1. Compositre, 47 species. 11. Piperacere, 12 species. 2. Cyperacere, 39 " 12. Convolvulacem, 12 " 3. Lobeliacere, 35 " 13. Malvacere, 12 " 4. Rubiacere, 33 " 14. Amarantacere, 9 " 5. Labiatre, 27 " 15. Araliacere, 8 " 6. Leguminosre, 20 " 16. Violacere, 6 " 7. Rutacere, 17 " 17. Pittosporacero, 6 " 8. Caryophyllacere, 14 " 18. Myrtacere, 6 " 9. Gesneriacere, 14 " 19. Goodeniacere, 6 " 10. Urticacere, 13 " 20. Thymelacero, 6 " Four other orders, Geraniacere, Rhamnacere, Rosacere, and Cucurbitacere, have five species each; and among the more im .. portant orders which have less than five species each ar~ Ranun. culacere, Ericacere, Primulacere, Polygonacere, Orchidacere, and Juncacere. In the a.bove enumeration the grasses (Graminacere) are omitted, as they were not described at the time Mr. Mann's X 2 |