presidext's address. 847 



wanted to permit of a connection in the past of the remotest 

 group of islands with the mainland. 



Tliere seems to be an argument in a circle as far as oceanic 

 insular floras are concerned. First of all it is assumed that if 

 the depth is over a certain amount — say, 1000 fathoms — former 

 land connection was not possible; then comes the study of the flora 

 and fauna of those islands which are thus situated, and those are 

 then looked upon as characteristic of such islands — other islands 

 have these characteristics — the conclusion is drawn that they 

 also have never been connected with the land. 



I shall not attempt to prove that important oceanic groups 

 like the Sandwich Islands and the Galapagos Islands wei-e once 

 connected with any of the continental areas. I leave that to 

 abler debaters than myself — like Captain Hutton and Dr. von 

 Jhering — but I wish merelj^ to draw attention to some of the 

 difflculties that the holders of the oceanic insular theory have to 

 contend with. 



First let me say that there are many islands, formerly held to 

 be oceanic islands, which are now acknowledged to have had a 

 former continental connection — such as New Zealand, the Fiji and 

 the Solomon Islands. Atolls and coral islands, and some islands 

 of volcanic origin are probably acknowledged by every one to be 

 trul}^ oceanic, and about these thei-e is no dispute. The ditticulty 

 lies in the determination whether such groups as the Samoan, 

 Tongan, Marquesan and other groups of the Western and Central 

 Pacific, the Sandwich Islands, Galapagos and some detached 

 islands like Pitcairn and Easter Islands come under this category. 



It is well known and acknowledged that there are about 200 

 species of plants the seeds of which stand immersion in salt water 

 for a certain time, and ai'e, therefore, capable of germination if 

 thrown up by the sea on to a favourable spot, and out of these 

 there is a smaller number which do not lose their germinating 

 powers after prolonged immersion. Then, again, there are some 

 seeds with a hard testa surrounded by pulp, which, after being 

 eaten by birds, may be conveyed to islands at short distances, or 

 perhaps for 50 or 100 miles, as the birds may be in the habit of 



