302 PLANTS OF NEW ZEALAND 



of flowering plants on the Southern Islands out of a total 

 number of 143 : Auckland Islands, 10 ; Campbell Island, 

 7 ; Antipodes Islands, 3 ; Macquarie Island, 3 ; Snares 

 Islands, 2. In addition to these, there are no less than 29 

 species not found on the mainland, but growing on more 

 than one of the southern Islands. On the three Kings Islands 

 five species are endemic, and three others are known only from 

 other outlying Islands (Cheeseman). In the Kermadecs only 

 5 species out of 115 are endemic, a smaller percentage than 

 might have been expected. 



Stilbocarpa polaris, the plant under discussion, is found on 

 the Auckland, Campbell, Antipodes, and Macquarie Islands. 

 It must not be confused with the equally fine S. Lyallii, 

 which is found on Stewart Island, and the islands of Foveaux 

 Straits. A full discussion of the origin of these remarkable 

 forms, found only in isolated spots of the earth's surface, 

 would be out of place here ; but the subject is of so much 

 interest and importance, that it cannot be passed over without 

 some slight reference to theories regarding it. It is obvious 

 that these plants may be divided into two groups, (1) those 

 that are very closely related to mainland forms, (2) those that 

 are not closely related to any species of the mainland. 

 Amongst the latter are some of the most magnificent plants 

 of the Flora (e.g., Pleurophyllum speciosum ; Myosotidium.) 



Now, there are two possible explanations of the distribution 

 of species limited to narrow areas and solitary islets : (1) it 

 may be due to relict endemism, that is to say, the plant was 

 once widely distributed, but has for some reason or other 

 become almost extinct, and now exists only on outlying 

 islands, or in remote corners of the mainland. Thus, to take 

 an example from the human race, the limitation of the once 

 widely distributed Kelts to Brittany, Wales, Ireland, and the 

 north of Scotland, is a case of relict endemism. (2) If, however, 

 the species has been developed on the off islands, or outlying 

 peninsulas, owing to special conditions existing there, then we 



