292 Carl Skpttsberg 



floras of the lands on either side o£ the south polar continent. I 

 was in the party, and I have taken an interest ever since in the 

 history of the Antarctic flora and have tried to collect data bear- 

 ing upon it. In 1915 I published an annotated list illustrating the 

 intimate relations between subantarctic America and New Zea- 

 land."^* After I came to examine some of the Pacific floras (espe- 

 cially in Hawaii, where a small number of Antarctic genera 

 occur, a strange sight in a Paleotropical insular world), I desired 

 to take up the study of this element. The taxonomic basis is clear 

 in respect to some groups, but in respect to others the position 

 and affinities are not so well known and conclusions therefore are 

 less safe. I have just had occasion to show how important mono- 

 graphic studies are, if we would arrive at something like definite 

 results."' Time has not permitted me to make a complete study 

 of the Antarctic flora, its history and migrations. I shall restrict 

 myself here to occurrences of the representation of presumably 

 Paleantarctic genera by geographically isolated species in the 

 high Polynesian islands. These occurrences are few but very 

 striking, and they offer a number of interesting and troublesome 

 problems. Much more numerous are those Antarctic genera 

 which, in the Pacific region, extend to New Zealand, south- 

 eastern Australia, New Guinea and, perhaps, Malaya without 

 occurring in Polynesia. They do not seem to present exacdy 

 the same problems as do the genera which are the subject of the 

 present study. Roads have been easier along the extreme western 

 border. 



Among the Antarctic-Pacific genera, more than one type of 

 distribution may be distinguished. It is convenient to recognize 

 one tricentric and one bicentric group. The former is represented 

 in the Australasian, American, and African sectors; the latter is 



* Superior figures refer to items in the bibliography at the end of this essay. 



