HuTTON AND IviKK. — Description of Arid Island. Ill 



of its flora approximated closely to that o£ the Little Barrier Island, whicli 

 it so nearly resembles geologically. A complete examination o£ Arid Island 

 and the Little Barrier would probably result in the discovery of other plants 

 common to both but absent from the Great Barrier besides those observed 

 by us. 



The flora of the island may be roughly divided into Ericetal, or plants 

 of the open land ; Sylvestral, or forest plants ; Littoral, or beach plants ; 

 and Uliginal, or marsh and swamp plants. It need scarcely be remarked 

 that these terms are not always capable of precise application. 



The greater portion of the central area of the crater and its ritn is 

 occupied by Ericetal plants ; in the lower parts, a dense growth of Pteris 

 esculenta, which often attains the height of six feet, intermixed with occa- 

 sional tufts of JPJwrmium tenax, renders all progress slow and laborious. On 

 higher parts and in open places the fern is supplanted by Leptosperimtm 

 scoparium and Pomaderris pliylicifolia, sparingly intermixed with bushes of 

 Coprosma rohusta, 0. lucida, Carmiclioelia mistralis, Leucopogon fasciculatws, 

 Vero7iica salicifolia, Coriaria ritscifolia, and other small shrubs. Agrostis 

 cemula, Leitcopogon frazeri, Drosera cmriculata, Lolelia anceps, Saloragis 

 micrantlia, Lagenopliora forsteri, &c., &c., were common amongst open fern, 

 together with the ubiquitous introduced plant JErigeroii canadensis. The 

 pretty OpMoglossum lusitanicum Avas seen on tuf aceous ledges, and was after- 

 wards observed in exactly similar habitats on the Little Barrier, but appeared 

 to be entirely absent from the Grreat Barrier. Many specimens had two or 

 more scapes springing from the same root, a peculiarity it shares with other 

 forms of the genus in New Zealand, although all the forms collected in the 

 northern hemisphere have invariably solitary scapes. On the highest points 

 of the island, as in fact of all islands and headlands in the north of New 

 Zealand, Astelia ianksii and Iletrosideros tomentosa were invariably found, 

 Astelia hanJcsii, we inay remark, is always rupestral in its habitat, never 

 epiphytal ; nor is it found at any great distance from the sea, so far as 

 our experience extends. Erom personal observation, we can testify it is 

 abundant on rocks at Mercury Bay, where we sought for it in vain " on 

 the limbs of trees," as reported in the " Handbook of the N. Z. Flora." 

 Astelia cimnitighamii is both epiphytic and rupestral, and is most frequently 

 found inland. 



The sheltered open spaces at the base of the cliffs on the exterior of the 

 crater, and large portions of the northern and southern sides of the interior, 

 are occupied by the Sylvestral portion of the flora in the crater itself, 

 forming a somewhat open bush, although few of the trees attain large 

 dimensions. As might be expected, the Pohutukawa (Metrosideros tomentosa), 

 is abundant, although greatly inferior in size and appearance to the fine 



