T. Kmx.—On the Dotany of Islands in the Hauraki Gulf. 449 
Te Ratoroa contains 204 acres. Its fora is chiefly remarkable for the 
profusion of Entelea, associated with Brachyglottis, Coprosma, Veronica, and 
other small shrubs. The plants of Motuora are of a similar character. 
Motukorea, or Brown’s Island, has an area of 150 acres. It is chiefly 
voleanic, and contains one of the most perfect craters to be found iu tho 
Auckland system. With the exception of the lava field, which forms a 
large portion of the lower part of the island, the whole has been laid down 
in grass, and presents no botanical features of special interest. In a few 
places, where water accumulates in spaces amongst the blocks of lava, or 
percolates through them from the sea, Typha latifolia, Scirpus maritimus, 
and other uliginal plants are found in some quantity. In other parts of 
the lava field a dense growth of bushy shrubs attracts attention. Olearia 
furfuracea and Metrosideros tomentosa occur sparingly, but the latter is 
usually of small size. 
The volcanic island of Rangitoto, which forms so prominent a feature in 
the scenery of the Hauraki Gulf, possesses greater interest to the botanist 
than any other island in the group. This arises less from a copious flora 
although the number of species is comparatively large—than from the 
remarkable state of the ligneous vegetation, which exhibits the utmost 
luxuriance of foliage and flowers on the most diminutive specimens, and 
from the peculiar conditions of growth, most of the plants springing 
directly from the face of the rocks or from the crevices between them. A 
brief description of the island will enable us better to understand the pecu- 
liarities presented by its flora. 
Rangitoto is roughly circular in outline, with deep indentations; its 
greatest diameter is about four miles; its least two and a-half miles; it is 
estimated to contain 5,044 acres, and is next iu size to Waiheke. Its base 
consists of an irregular lava field, rising towards the ceutre at an angle of 
four or five degrees. From near the centre the scoria cone, which forms 
the crater, rises at an angle of about 85 degrees to the height of 980 feet. 
The cone is double, but the outer one has been carried away in places; the 
inner and more clevated cone forms the largest and best preserved crater 
to be found in the Auckland system. It is considered to be the latest 
manifestation of voleanie activity in the Waitemata district. Although 
ouly 200 feet higher than the highest point of Waiheke, its isolated peak is 
frequently surrounded by clouds, while the whole of the adjacent isthmus 
is suffering from want of rain. 
The lava fiell, which forms the chief portion of the island, is extremely 
rough aud difficult of examination, being broken up into chasms, ravines, 
and irregular depressions ; for the most part progress can only be made by 
leaping from one sharp-edged block of scoria to another, or by scrambling 
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