MACLOSKIE: CHARACTER AND ORIGIN OF THE PATAGONIAN FLORA. 951 



many as 276 species and 50 varieties. The Dicotyledones have about 

 i, 600 species, and 240 varieties, in 410 genera, and 92 families. 



An examination of the affinities of species and of their geographical dis- 

 tribution leads to the conclusion that the Patagonian lands constitute a 

 true botanical region, well characterized yet not sharply limited by nat- 

 ural boundaries. Thus we find the native species settling into diverse 

 groups, each presenting its own distributional problem, and bearing testi- 

 mony which has not yet been fully interpreted. 



1. We have a large number, about 120 species, of plants which are 

 somewhat isolated, and characteristic of the region. A number of these 

 have become famous, and many more are deserving of attention. Some 

 of the remarkable genera are almost confined to the region, and of the 

 other genera several species are confined to it. 



2. On the other hand we note about 150 genera of plants character- 

 istic of Temperate and Warm-temperate climates elsewhere, and most of 

 them widespread, yet not known in Patagonia. Some of these are here 

 represented by allied, often peculiar, forms. These facts taken together 

 favor a theory of long-continued geographical demarcation, or partial 

 isolation, between this and other lands of similar latitudes. 



3. We also observe a large number of examples of the discontinuous 

 distribution of identical or closely allied species ; several of them remark- 

 able ; but most surprising is their large number. By the help of Engler 

 and Prantl's Pflanzenfamilien we have noted as many as 106 instances 

 of these (including a few cases of plants recently introduced). A well- 

 known case of this discontinuity is allied species of Araucaria found here 

 and on Norfolk Id. : others are the beautiful Veronica elliptica in Fuegia, 

 West Falkland and New Zealand ; allied species of Gaimardia, Rost- 

 kovia, Laitrelia, the Uncinia sinclairii, Ourisia species, Gunnera, and 

 Carex darwinii var. urolepis (see page 961), unite Patagonia with New 

 Zealand ; whilst some others inhabit Tasmania, and some (as species of 

 Pernettyd] are also in South Australia. Again some peculiar sections of 

 large genera, as of Myosotis and of Plantago, and Fagus, link together 

 the widely separated southern lands. Kcenigia (Macounastnim] has one 

 species found both in Arctic islands, and in Himalaya, and another species 

 in Fuegia. Bryodes has a species in Mauritius, and another in Magellan. 

 Eriogonum, so characteristic of the Western United States, is represented 

 by a species in Patagonia, and the common European Geum urbanum 



