METHODS OF TRAVELLING. 195 
of the light fruit, commonly called the “seed.” This method of 
flying, after the manner of a parachute, is a common feature of plants 
of the daisy family; also the willow-herbs (Hpilobiwm) and New 
Zealand jasmines (Parsonsia) travel in this manner. But the dis- 
tance gained may easily be misjudged, as in the case of the thistle ; 
for thistledown it frequently is, pure and simple, the heavier seed 
having become detached quite early on. 
Seeds and fruits, however, do not require any special flying- 
apparatus to enable them to be carried for quite a considerable 
distance by the wind. Where small stones are raised high in the 
air, as is frequently the case during heavy gales, there is hardly a 
species of New Zealand plant which cannot have its seeds dispersed 
to a longer or shorter distance ; in fact, except with regard to those 
plants of entirely sheltered habitats, no special apparatus for dis- 
persal seems to be required—z.e., so long as there is no broad 
water to cross. 
Birds undoubtedly play a considerable part in the dispersal of 
seeds. Berries they eat, and the seeds, as part of their excreta, are 
“sown ’’ under favourable conditions. Other seeds or fruits adhere 
to the feathers or other parts of the bird—the feet, for instance. 
The fruits of the piripiri (species of Acaena) and of the hooked sedges 
(Uneima) are specially suited for distribution by animals. Yet, 
strange to say, no species of either of these genera occur on the 
Kermadec Islands, while both the Chatham and the subantarctic 
islands have each at least one variety of Acaena Sanguisorbae peculiar 
to the group. 
The question of how species travel long distances is of especial 
moment with regard to those of the high mountains, for they must 
frequently travel considerable distances over country hostile to their 
settlement. If the actual high-mountain plants be alone considered, 
only about 7 per cent. possess succulent seed-containing food attrac- 
tive to birds, but 23 per cent., including the ferns, are specially fitted 
for carriage by wind. Add to the above the species having hooked 
fruits, and the orchids with their minute seeds, and the percentage 
rises to 36. But there are a considerable number of species in 
addition to the above that might readily become attached to birds, 
so that it seems safe to conclude that one half the species may be 
widely distributed by means of wind or birds, while the other half 
are not suitable for dissemination under ordinary circumstances. It 
