ArmstronG.—-On the Flora of the Province of Canterbury. 335 
cress, Nasturtium officinale, has proved very troublesome in the rivers, 
where it attains a size and strength quite unknown in its native country. 
Another aquatic, the Canadian pond-weed, Anacharis canadensis, of recent 
introduction, is now abundant in the Avon and other rivers, where it 
seriously interferes with drainage and navigation. I am of opinion that 
the fact of the naturalization of foreign plants in New Zealand furnishes a 
key to the origin of large portions of the floras of other countries, notably 
of England and Italy. 
No doubt many of the plants now considered indigenous to those 
countries have been introduced through the indirect agency of man— 
perhaps very many generations ago. I think that this theory is borne 
out by the fact that all countries widely separated from the great masses 
of land, and cut off from communication as New Zealand was before its 
discovery by Europeans, have very few species in common with other 
countries, and these chiefly such as might be carried by the sea, by stray 
birds, or by strong winds. 
I have included in my catalogue of introduced plants a few species 
which are usually considered indigenous, but, after a careful examination 
of all the evidence obtainable, I am satisfied that they are really introduced, 
and have no claims to be considered indigenous ; these are,— Cyperus tenellus, 
Sporobolus elongatus, Keleria cristata, Alopecurus geniculatus, Picris hiera- 
cioides, and Polygonum aviculare. 
Economic Plants of Canterbury.—The most important economic plants of 
the province are the timber trees, which have already been mentioned 
when describing the various districts in which they are found. In the way 
of plants fitted for human food, the native flora has very few species and 
they are in every way inferior—the two or three vegetables cultivated by 
the Maoris not being indigenous. The fruits eaten by the natives of the 
South Island were the berries of the pines, those of the hinau, the karaka, 
the poroporo, Solanum aviculare, and Aristotelia racemosa ; few or none of 
which would be considered eatable by Europeans. The sea-side cress, 
Lepidium oleraceum and the New Zealand spinach, Tetragonia trigyna, have 
been used by English settlers as pot-herbs. Plants yielding fibre are both 
numerous and important. Foremost among them are the two species of 
flax or Phormium, which are now so well known throughout the world. 
The two kinds of cabbage-tree or Cordyline yield a fine soft white fibre, 
nearly as strong as and probably more valuable than the Phormium. Astelia 
grandis also yields a soft brown fibre of considerable strength, and is easily. 
cultivated. Some of the coarser kinds of grasses, such as the tussock, Poa 
cespitosa, Aira, Apera, etc., would no doubt yield fibres of some value. 
The whole of the fibre-plants mentioned here are very easy of cultivation, 
