Ba an 
The Plant Formations. — Salt-water Associations. 63 
become almost a scrambling liane with shoots attaining more than ı m in 
length. 
Speaking of coastal epharmony generally, there is certainly a strong re- 
lation between the form of the species that are exposed to the true maritime 
environment and the master-factors of the latter. This is well seen in the 
suceculence of certain herbs &c. of a salt substratum, in the remarkable 
adaptations of the mangrove and in the sand-binding form of certain dune- 
plants belonging to different families or genera. At the same time there are 
many true coastal species whose form and structure afford no evidence of 
proximity to the sea, but these are rather plants of sheltered localities where 
coastal conditions are absent-or much modified, and their presence is to be 
attributed rather to the mildness of the maritime climate than to any coastal. 
adaptations. 
Chapter IV. The Plant Formations. 
1. Salt-water Associations. 
a. Ihe Sea-weed communities'). 
About 450 species of marine Algae have been recorded for New Zealand 
of which probably one half are endemic, while a considerable number are of 
wide distribution. The actual range of the different species along. the coast is 
still very imperfectly known, while accurate details as to their bathymetrical 
range are altogether wanting. It is clear however that sea-temperatures, in 
large part, govern their distribution in latitude, but no data are available as to 
local coastal and seasonal temperatures. All that can be said is that many 
species appear to be confined to the colder waters of the Fiord, South Otago 
and Stewart distriets, while a few do not occur outside the Northern botanical 
province. Further, the study of the New Zealand Algae has hitherto been 
entirely floristic, so that quite general statements as to gas synecology must 
be made. 
The usual Ans is shown on the New Zealand coast. Near high- 
water mark, there are a few species of green sea-weeds, usually in no great 
quantity, consisting chiefly of cosmopolitan forms of Ulva and cosmopolitan 
and local forms of Enteromorpha with abundance of the narrow ribbons of 
Scytosiphon lomentarius 30 cm, or more, long. Where there are modera- 
tely shallow rock-pools near low-water mark, brown algae_ re | 
though here too’ a few ne ya e. ” : me vestta f ing, 
little < owdk 
