340 PLANTS, SEEDS, AND CURRENTS 



pumila reached the Australian and New Zealand region from Chile, 

 there is good foundation for the view that it is a gift from either 

 Australia or New Zealand, preferably the latter, to South America. 

 Accepting that inference, the fact that it has been recorded only 

 from the western side of the continent, namely, from Chile, clearly 

 indicates the route taken in its ocean passage, that is, from the 

 west, which is under the circumstances the only route rendered 

 practicable by the winds, the birds, and the currents. 



The indications supplied by Carex pumila derive fresh interest 

 from those offered in the cases of the two other species, C. darwinii 

 and C. trifida, which, with the four before named, make up the six 

 species held in common between southern South America and the 

 Australian and New Zealand region. These two Car ices have been 

 found nowhere else on the globe than in the southern extreme of 

 the American continent, in New Zealand, and in the islands near 

 and to the south of it. Presumably there has here been some com- 

 munication between these two widely separated regions; and the 

 question that at once presents itself is whether South America 

 supplied these two species to the New Zealand region, or whether 

 it received them from that source. In either case it must be assumed 

 that the sea-bird that transported the seed followed the westerly 

 winds in its ocean traverse. This being granted, the case of C. darwinii 

 raises a curious point. Since this species is well distributed over 

 the Southern Andine region and in Fuegia, and since it occurs only 

 in the Chatham Islands in the New Zealand and Australian region, 

 the seed must have been carried eastward from Cape Horn. This 

 route involves an ocean passage twice as great as that which would 

 be implied in the passage westward against the westerly winds from 

 Cape Horn to the Chatham Islands. But it would be assisted by 

 the several islands in the Southern Ocean that serve as resting- 

 places for the sea-birds that are ever flying round the globe in the 

 latitudes of the Roaring Forties. The evidence of the other species, 

 Carex trifida, is indeterminate, since it is well distributed in South 

 Chile and the Falklands Islands in the one region, and in New Zealand 

 and the neighbouring Antarctic Islands in the other. 



The direct Sphagnum and Carex Connections between Fuegia 

 and the New Zealand and Australian Region. — From the above 

 remarks it may be inferred that the parallel already traced between 

 Sphagnum and Carex may be further extended to the species common 

 to the southern extreme of South America and the Australian and 

 New Zealand region. But the parallel is not complete. Whilst 

 it has been shown that the two species of Sphagnum common to 

 these widely separated regions must have been derived in each case 

 from northern latitudes on the same side of the globe, South American 

 from North America and Australian from Asia, this applies to only 

 three of the six Carices common to the two regions. In the case of 

 the others a communication across the Southern Ocean is implied, 

 in one species from Australia or New Zealand to Chile, in another 

 from Fuegia to the New Zealand area, whilst in the third there is 

 nothing to indicate which region was the giver and which was the 

 recipient. 



