Page:Journal of botany, British and foreign, Volume 34 (1896).djvu/372

 344 THE DISPLACEMENT OF SPECIES IN NEW ZEALAND. amalgamated with them, to the great benefit of the stock- grower. Microlana stipoides and Danthonia pilosa are fair examples of this group. Replacement by Epacrids. One of the most interesting instances of replacement that has been observed up to this time is now in progress on the Te Karaka flats, between Papatoitoi and Drury, in the Auckland District. These flats for many miles are clothed with a dense, but not always luxuriant, growth of manuka, manuka-raunui [Leytmpermum eri- coides, Dracoj^hyllum Urvilliamim), mingimingi (Cyathodes acerosa), &c., the manuka being the prevailing plant. Rather more than forty years ago the late Dr. Sinclair and General Bolton discovered the beautiful Ejpacris 2^urjmrasce7is, a native of New South Wales, in this locality, when it was rightly considered by Sir Joseph Hooker to have been introduced.* Fifteen years elapsed before it was seen by other botanists, when it was found in several places on the flats, presenting the aspect of a truly indigenous plant, and attaining the height of from 2 ft. to 6 ft. or more. From the great quantity in which it was found I was erroneously led to consider it indigenous, and this conclusion has been generally accepted. More recently f it has been observed in localities fully twenty miles distant. In 1875 three plants of another species {E. microphylla) were discovered by A. T. Urquhart, Esq., in the same district. This species is also a native of New South Wales, but has a wider range, extending to Queensland, Victoria, and Tasmania. In three years the plant increased to such an extent that it formed "a dense mass 60 yards in circumference, the intermediate vegetation — Leptospermum, PomaderHs, and Pteris — being almost completely destroyed."! In 1887 I had the pleasure of visiting the habitat under the guidance of Mr. Urquhart, and found that not only had the area occupied by the plant been greatly extended, but that colonies had been formed at a greater or less distance from the original centre, and would in their turn form new centres of distri- bution. Mr. Urquhart also pointed out a very old specimen of another species, E. pidchella, also a native of New South Wales : this was surrounded by numbers of young plants, which were producing perfect seed, and increasing at a rapid rate. My friend informed me that he had discovered a colony of this species at some distance from the parent plant, but, unfortunately, I had not time to visit it. These three species were alike extending their area mainly in the direction of the prevailing winds, and would, I am convinced, be able practically to replace the indigenous vegetation over the entire area if not interfered with by man. This instance of replacement is replete with interest, as it is almost the only case in which there is clear evidence of the seeds of phanerogamic plants having been carried by aerial currents over a distance of from 1200 to 1400 miles and becoming established in a new country. t Trans. N. Z. Inst. ii. (1869), 107. + Trans. N. Z. Inst, xviii. (1881), 364.
 * Fl. N. Z. ii. 321, 334.