RXV INTRODUCTION. 
As representatives may be designated the Alani and Olapa in 
Pelea and Cheirodendron. The prevailing trees are indeed Metro- 
sideros polymorpha and Acacia Koa, but although they reach here 
their greatest development in size and number they are not 
confined to this zone, but extend above and descend below it. 
It is the home of all Rutaceous and most Araliaceous trees, the 
ubiquitous Dodonaea viscosa, Alphitonia, and Coprosma. The ferns 
luxuriate in it, and tree-ferns attain only here their full dimen- 
sions. Old trunks are wrapped in creeping ferns, mosses, and 
lichens. Here also the Lobeliaceae, the peculiar pride of our 
flora, exhibit their most striking forms, but invariably in isolated 
individuals. The upper limit of this zone may be drawn at an 
elevation of 5000 to 6000 ft. It then passes gradually into the 
next 
4. The upper forest-zone. This extends as high as 8000 or 
9000 ft. and is characterized by stunted trees, chiefly the 
Mamani (Sophora chrysophylla), Cyathodes, the Naeo (Myoporum), 
arborescent Raillardiae, Wikstroemiae, and Coprosma Menziesii. 
Between them luxuriate shrubby Compositae, Raillardiae, Dubautia, 
Campylotheca, and Artemisia, Strawberries, Brambles, and the 
Ohelo, Vaccinium. Ferns are scarce and mostly belong to widely 
spread species or stand near them, as Asplenium Trichomanes, A. 
Adiantum nigrum, Polypodium pellucidum, Aspidium aculeatum, 
Cystopteris. Shrubby Geranium and silvery leaved Argyroxiphium 
extend beyond the zone, at least on Mauna Kea, to the upper 
limit of vegetation, which may be placed at 11,000 ft. for that 
mountain. Santalum belongs to this zone and to the upper belts 
of the middle forests. 
5. A place apart must be assigned to the bog- flora of the 
high table-land of Kauai and of the broad top of Mt. Keka, on 
West-Maui. The turfy soil is covered with tussock-like Graminaceae 
and Cyperaceae, all quite peculiar species, with Sphagnum, creeping 
orms of woody Metrosideros, Cyathodes, Geranium, Lysimachia, 
and a number of rare, mostly single, representatives of genera 
which have their home in the Antarctic regions, New Zealand, 
the Falkland Islands, southern Andes, ete. 
The breadth of these zones, particularly of the first and 
second, varies considerably with their exposure; thus, under the 
lee of Haleakala and Mauna Loa the second zone rises to a 
height of 2500 ft. 
Another peculiarity in the physiognomy of the vegetation has 
to be noticed. Under the lee of the high mountains of Hawaii 
