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THE JOURNAL OF BOTANY 



Island, Macauley Island, Citrtis Island, and French Keck — and 

 are situated half-way along the submarine ridge which connects 

 New Zealand with the Tonga group. They are volcanic and 

 composed of tufas. Sunday Island is the largest of the group, 

 and its coast is rocky save for the gravelly beach in Denham Bay 

 on the south-west side, and some sand on the north shore. These 

 islands lie far away from any land from which they could have 

 derived their flora and fauna ; and hence their great interest to 

 students of geographical distribution. The preponderance of the 

 flora is of the New Zealand type, bringing the islands into the 

 New Zealand biological region. Dr. Cockayne has made the 

 Kermadecs a separate province of that region ; but Mr. Oliver 

 endeavours to show that they unite with Lord Howe Island and 

 Norfolk Island to form a natural division, for which he proposes 

 the name " subtropical islands province." 



The marine algae collected by Mr. Oliver were sent to Mr. 

 E. M. Laing, who very kindly invited us to identify them. He 

 intends to publish a list of them himself in New Zealand, but 

 suggests that in the meantime we should give the names in this 

 country. 



As regards the geographical distribution of the species, it will 

 be seen that none of them is endemic unless it be the Galaxaura, 

 but that the majority are found in New Zealand. Mr. Oliver {loc. 

 cit. p. 156), writing on "Dispersal," says: "The nature of the 

 material cast up on the shores of Sunday Island points to the 

 south or south-west as the direction from which the strongest 

 and most frequent [ocean currents] reach the group. Several 

 kauri (Agathis aiistraUs Salisb.) logs, some bearing brands of New 

 Zealand firms, are lying on the shores of Sunday Island, and on 

 the north coast is a balk of Oregon pine, supposed to have formed 

 part of the cargo of the ' Elingamite,' wrecked on the Three Kings 

 Islands in 1903. Again, during the months of July to October, 

 1908, when strong westerly winds prevailed, a large amount of 

 seaweed was cast up in Denham Bay. ... It is evident that a 

 strong ocean current flows from New Zealand in a north-easterly 

 direction ; and this in my opinion is sufficient to account for the 

 preponderance of New Zealand forms in the flora of the Kermadec 

 Islands." 



A study of the charted ocean currents of the South Pacific 

 confirms this view, and shows at once that the Kermadecs are in 

 a very interesting position. A. branch of the great South Equa- 

 torial Current sweeps down to the south-west past Samoa, Fiji, 

 and the Friendly Islands. It runs on past Norfolk Island and 

 Lord Howe Island, and skirts down the coast of the Continent of 

 Australia (East Australian Current). Then colliding with the 

 cold subantarctic water of the strong West Wind Drift, it is 

 deflected, and now runs up north-east past the islands of New 

 Zealand, and strikes across to the Kermadecs. Here it joins 

 another branch of the South Equatorial Current, which has swept 

 down south from the Friendly Islands. The conjoined currents 

 pass away to the south-east. Thus the Kermadec group is washed 



