PRKSIDKNT S AODRKSS. XV 



Nortli America but unknown to tho Europe.'in Hora. Tlio Irish 

 Hlmy feni is also non-European, and is a native of the Azores. 



About twenty species and sub-species of plants growing in 

 Ireland are not met with in Britain, and, on the other hand, 

 many British species have not reached Ii-eland. Some are 

 restricted to the East of England, others have arrived on the 

 south coasts and have travelled up the western sliores; and, 

 again, others are Alpine, vscattered here and there on the highest 

 hills. Some species are clearly natives, others colonists or 

 aliens. 



If we turn to the great continent of North America, we 

 ftnd that the flora as we pass southward from Canada through 

 the United States does not alter essentially, but whilst becoming 

 more luxm'iant as we reach the extremity of Florida, it still 

 preserves the character of a temperate flora. But if we cross 

 the Straits to the Bahama Islands, a distance of only about fifty 

 miles, we find that almost all the North American t}'pes of 

 plants have disappeared, and that we are in the midst of a 

 tropical flora mostly identical with that of Cuba. The inference 

 of some former connection between these two last seems evident. 



The discrepancies and resemblances between the flora of New 

 Zealand and that of Australia, the nearest continental land, are 

 so remarkable that their relationships have proved a ditficult prob- 

 lem. New Zealand and Australia both possess temperate floras 

 which have considerable resemblance, but apparently at some 

 recent period Australia has acquired remarkable accessions, among 

 them thet Eucalyptiis and other trees that give such a character 

 to the Australian landscape. The tropical flora of New Zealand 

 appears to have been derived fi'om north-east Australia at a 

 time when that part was separated fi-om the temperate and 

 southern parts by a channel, but united to New Zealand in a 

 direction where the sea is still comparatively shallow. In many 

 slands there is almost an identical flora with that of adjacent 

 continents, indicating former union. In the Sandwich Islands, 

 on the other hand, far away in mid-ocean, the flora is rich 

 and almost three-fifths of the species are indigenous 



