90 Transactions. — Miscellaneous. 
turbed, and the sand is so placed as to be capable of retaining moisture, it 
is generally covered with vegetation (more or less luxuriant according to 
the degree of moisture present), of the special character which affects this 
description of habitat. I give at the foot of this paper a list of the most 
conspicuous dune plants indigenous to New Zealand, many of which would 
be found valuable in other countries. 
Now this vegetation confines the sand, and would, if undisturbed — 
by man, or by grazing or burrowing animals, entirely prevent its motion 
under the influence of the wind, whilst, wherever the surface is not 
confined by plant growth or by a crust of vegetable matter, the sand 
is constantly rolled forward in the direction of the prevailing winds. 
Instances, indeed, are abundant in other countries, of populous and 
fertile districts having by this means been converted into barren wastes. 
A recent example of this was observed in connection with the dunes which 
lie between the Adour and the estuary of the Gironde, on the west coast of 
France, the sands of which were found, where not fixed by vegetable 
growth, to advance eastward at a mean rate of about sixteen and a half feet 
a year, the result being that a large extent of fertile land was destroyed before 
effectual measures could be taken to arrest the evil. . Other instances of the 
mischief which results from disturbing the vegetation upon the surfaces of 
sand dunes will be given in the sequel, whilst, to bring the matter home, I 
may mention that Mr. Hadfield (who occupies a tract of land between the 
rivers Otaki and Ohau, on the west coast of this Provincial District) informs 
me that the sands of the dunes between those rivers are advancing inland 
at a rapid rate and threaten great injury, unless effectual steps be taken to 
prevent it. I have observed the same thing occurring on the shores of 
Pegasus Bay, but in less degree owing to the fact that the strong westerly 
winds which are frequent there, blow off shore, and prevent any rapid 
inland extension of the sand under the influence of the easterly winds which 
prevail on that coast. 
It has been a question of interest in Europe, whether, and to what 
extent, the generally bare condition of coast dunes is to be attributed to the 
improvidence and indiscretion of man, and recent investigations seem to 
have shown that, in almost every case, the inland advance of dune sands 
may be traced to man’s interference with natural operations. A patent 
instance of this is given in connection with the dunes of the Frische 
Nebrung, on the coast of Prussia. It is related by Willibald Alexis (as 
quoted by Mr, Marsh, in his interesting and valuable work on Physical 
Geography), “that the dunes of the Nebrung were formerly covered with a 
great pine forest, which extended to the water’s edge, and bound, with its 
roots, the dune sand and the heath uninterruptedly from Dantzig to Pillau, 
