134 Transactions. 



Three plants occupy practically the whole of the flat^ — viz., Mariscus 

 ustulatus, Scirpus nodosus, and Ipomoea pes caprce. Mariscus ustulatus 

 occurs all over the fiat, but more sparingly near the forest, where it is re- 

 placed by Scirpus nodosus and Ageratum. conyzoides. Ipomosa pes caprce 

 grows almost everywhere, mixing with both Mariscus and Scirpus. Its 

 long trailing stems are only driven back by the waves on one side and by 

 the shade of the forest on the other. A few shrubs of Myoporum Icetum 

 occur here and there, while there is an undergrowth among the Mariscus 

 and Ipomoea, chiefly composed of Stellaria media, Euphorbia Peplus, and 

 Cynodon DactyJon. Along the sea -edge, where the gravel takes the nature 

 of a dune, Calystegia Soldanella and Tetragonia expansa occur. 



There is ev dence that another plant — Sccevola gracilis — now almost 

 entirely killed by introduced sheep and cattle, formerly took an important 

 part in the formation. In an enclosure at the south end of Denham 

 Bay, where these animals are not allowed, the vegetation is dense, about 

 half a metre high, and composed principally of Sccevola gracilis and Scirpus 

 nodosus, with Ipomoea pes caprce growing among them. Here also are 

 found Imperata Cheesemani and Danthonia pilosa. 



2. Inland Edaphic Formations. 



The plant formations occurring in all places on Sunday Island where the 

 nature of the soil inhibits the growth of forest (except the areas occupied 

 by the coastal, young, and introduced formations) are included under this 

 heading, and naturally fall into three groups, which will be described in the 

 order of their probable appearance. Forest, being the only climatic forma- 

 tion, is kept under a separate heading, though true forest possibly existed 

 on Sunday Island before there were any swamps or lakes. 



(a.) Rocks and Cliffs. — On Sunday Island it may be said with regrrd to 

 chif vegetation that some of the plants now most characteristic of it are 

 those which goats search out and suppress in the forest. This is certainly 

 the case with Asplenium. Shuttleworthianum and Veronica hreviracemosa. 

 Certain plants, however, such as Lagenophora petiolata and Lobelia anceps, 

 are found in nearly all rocky places in the forest. Other species usually 

 occurring in rocky situations are Hydrocotyle nioscJiata, Coprosma petiolata, 

 Carex Forsteri insularis, Sccevola gracilis, Cyclopliorus serpens, Peperomia 

 Endlicheri, Poa polyphylla, Mesembryanthemum australe, and Psilotum tri- 

 quetrum. 



The rock-vegetation is well developed on the cliffs at the back of the 

 Terraces. These cliffs are of an exceptionally dry character, face north, 

 and are inaccessible to goats. Where there is a crevice or ledge affording 

 the slightest hold for soil, plants will be found. The chief members are 

 Cyclophorus serpens, Lobelia anceps, Asplenium. Shuttleworthianum, Poa 

 polyphylla, Peperomia Endlicheri, and Mesembryanthemum australe. A plant 

 of Coprosma petiolata was also seen. 



On the cliffs above Denham Bay, now, owing to the presence of inhabit- 

 ants in the bay, practically free from goats, are found Veronica breviracemosa, 

 Coprosma petiolata, Lobelia anceps, Lagenophora Forsteri, and Carex Forsteri 

 insularis, besides Hydrocotyle moschata in damp places. On an open rocky 

 slope Sccevola gracilis covers the ground ; mixed with it is a little Dan- 

 thonia pilosa. 



A cliff in the crater at the base of Moumoukai contains the following 

 plants : Poa polyphylla, Cyclophorus serpens, Sccevola gracilis, Erechtites 



I 



