1914] CURRENT LITERATURE 97 



much of the non-swampy ground where the subsoil is composed of finer mate- 

 rial. Above the coarser dry soils the Empetrum heath association dominates 

 with an abundance of low evergreen shrubs. In wet depressions the Falkland 

 representative of the peat bog occurs in the Astelia association, where several 

 seed plants replace Sphagnum and forming low absorptive cushions are largely 

 responsible for the immense layers of peat, several meters thick, that furnish 

 the only fuel on the islands. 



The tops of the highest mountains (only 700 m.) are covered with Empe- 

 trum heath, but a semialpine character is given to the vegetation by the presence 

 of many cushion plants, among which the two remarkable umbelliferous genera 

 Bolax and Azorella are conspicuous. 



The author gives interesting notes on the flowering of many species, and 

 also classifies the plants according to the ''biological types" of Raunkiaer. 

 He points out that the results hardly support Raunkiaer's characterization 

 of the islands as possessing a "chamaephyte climate," in spite of the large 

 percentage of chamaephytes and hemicryptophytes, since both classes are 

 evergreen in the Falklands, showing slight vegetative periodicity, simply some 

 arrest of growth during the winter. Among the numerous other interesting 

 facts regarding various phases of the vegetation, the presence of a very con- 

 siderable number of ferns belonging to the rainy west coast of Chile and Fuegia 

 is worthy of notice, and is made conspicuous upon the map of the author's 

 travels. 



Tierra del Fuego 2 * shows the passage of the grassy heath to the steppe, a 

 transition to deciduous forest dominated by Nothofagns pumilio and in higher 

 altitudes by N. antarctica, while the western half is covered with an evergreen 

 rain forest in which N. betuloides and Drimys Winteri are the chief members. 

 The distribution of these formations is shown upon an excellent map which 

 has been extended in a more recent publication 24 to include South America 

 to latitude 41 S. The evergreen rain forest is shown to extend to 48 S. without 

 striking change. Within this southern extension of rain forest, the number of 

 species is small and the precipitation so evenly distributed that little periodicity 

 seems to be shown. On account of the rather sudden change due to a great 

 increase in the number of species, Skottsberg has selected the parallel of 48 S. 

 as the northern boundary of the Magellan province of the subantarctic region. 

 North of this line, not only is the forest richer in species, but there is more 



une 



Andes 



gnomische 



Sudpolar Exped. 1901-1903. 4: Lief. 9. pp. 63. pi. 3 and map. 



909 



34 Skottsberg, C, Botanische Ergebnisse der schwedischen Expedition nach 

 Patagonien und dem I euerlande 1907-1909. I. Ubersicht iiber die wichtigsten Pflan- 

 zenformationen Siidamerikas S. von 41 , ihre geographische Verbreitung und Bezie- 

 hungen zum Klima. K. Svensk. Vetensk. Handl. 46: no. 3. pp. 28. map. 1910. 



