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Show 470 ISLAND LIFE. [PART II. thouO'h chiefly developed in temperate Australia, extend into the ~·opical or sub-tropical portions of it, and may well have reached New Zealand by the same route. On the other hand we fin-d but few New Zealand genera certainly derived from Australia which are especially tempe~·ate, and it may be as well to give a list of such as do occur w1th a few remarks. They are sixteen in number, as follows:- 1. Pennantia (1 sp. ). This genus has a species in Norfolk Island, indi-cating perhaps its former extension to the north-west. . 2. Pomaderris (3 sp.). Two species are common to ;rempera~e Australta and New Zealand indicating recent trans-oceamc m1grat10n. 3. Quintinia (2 sp.). This genus has winged seeds facilitating migration. 4. Olearia (20 sp.). Seeds with pappus. . . 5. Craspedia (2 sp.). Seeds with pappus. Alpine; iden~ical w1t~ Australian species, and therefore of comparatively recent mtroducti_on. . 6. Celmisia (25 sp.). Seeds with pappus. Only three Australian spemes, two of which are identical with New Zealand forms, probably therefore deriYed from New Zealand. 7. Ozothamnus ( 5 sp. ). Seeds with pappus. 8. Epacris (4 sp.). Minute seeds. Some species are sub-tropical, and they are all found in the northern (warmer) island of New Zealand. 9. Archeria (2 sp.). Minute seeds. Tasmania and New Zealand only. 14. Alternanthm·a. Tropical Australia, India, and S. America. 15. T1·etmnthera. Tropical Australia, Tropics. 16. Santalum. Tropical and Sub-tropical Australia, Pacific, Malay I slands. 17. Carumbium. Tropical and Sub-tropical Australia, Pacific Islands. 18. Elatosternma. Sub-tropical Australia, Asia, Pacific Ialands. 19. Peperomia. Tropical nnd Sub-tropical Austmlia, Tropics. 20. Piper. Tropical and Sub-tropical Australia, Tropics. 21. Dacrydiurn. Tasmania, Malay, and Pacific Islands. 22. Dammam. Tropical Australia, Malay, and Pacitic Islands. 23. Dend-robium. Tropical Australia, Eastern Tropics. 24. Bolbophyllurn. Tropical and Sub-tropical Australia, Tropics. 25. Sm·cochiltts. Tropical and Sub-tropical Australia, Fiji, and Malay Islands. 26. Freycinetia. Tropical Australia, Tropical Asia. 27. Co1·dyline. Tropical Australia, Pacific Islands. 28. Dianella. Australia, India, Madagascar, Pacific Islands. 29. Cyperus. Australia, Tropical regions mainly. 30. Firnbristylis. Tropical Australia, Tropical regions. 31. Paspalurn. 'l'ropical and Sub-tropical grasses, 32. Isachne. Tropical and Sub-tropical grasses. 33. Spm·obolus. Tropical and Sub-tropical grasses~ CTIAP. XXII.) THE FLOUA OF NEW ZEALAND. 471 10. Logania (3 sp.). Small seeds. Alpine plants. 11. Hedycarya (11:lp.). 12. Chiloglottis (1 sp.). Minute seeds. In Auckland Islands; alpine in Australia. 13. Prasophyllum (1 sp.). Minute seeds. Identical with Australian species. 14. Orthoceras (1 sp.) Minute seeds. Close to an Australian species. 15. A~epyrum (1 sp.). Alpine, moss-like. An Antarctic type. 16. D10helachne (3 sp.). Identical with Australian species. An Mvned grass. We thus see that there are special features in most of these plants that would facilitate transmission across the sea between temperate Australia and New Zealand, or to both from some Antarctic island; and the fact that in several of them the species are absolutely identical shows that such transmission has . occurred in geologically recent times. Species common to }lew Zealand and Australia mostly Temperate jo?·ms.-Let us now take the species which are common to New Zealand and Australia, but found now here else, and which must therefore have pas~ed from one country to the other at a more recent period than the mass of geneTa with which we have hitherto been dealing. These are ninety-six in number, and they present a striking contrast to the similarly restricted genera in being wholly temperate in character, the entire list presenting only a single species which is confined to sub-tropical East Australia-a grass (Apera arundinacea) only found in a few localities on the New Zealand coast. Now it is clear that the larger portion, if not the whole, of these plants must have reached New Zealand from Australia (or in a few cases .Australia from New Zealand), by transmission across the sea, because we know there has been no land connection during the Tertiary period, as proved by the absence of all the .Australian mammalia, and almost all the most characteristic Australian birds, insects, and plants. The form of the seabed shows that the distance could not have been less than 600 miles, even during the greatest extension of Southern New Zealand and Tasmania ; and we have no reason to suppose it to have been Jess, because in other cases an equally abundant flora of identical species has reached islands at a still greater distance |
