48 BOTANY. 



tenax, Areca sapida, <fcc. Van Diemen's Land and New Holland : Protea- 

 ceae, Epacride», Leptospermeae. Chili and Buenos Ayres : Fagus, Laurelia, 

 Persea, Weinmannia, Coriaria, Mjrtus, &c. 



5. Colder Temperate Zone. 45° — 58° of latitude. Mean tempera- 

 ture 43° — 53|° F. ; minimum summer temperature on the Avest coast 56^° ; 

 in the interior of the continent 68° ; minimum winter temperature in the 

 interior of Europe 14°. 



Northern hemisphej'e ; Europe : Corylus, Viburnum, extended green mea- 

 dows ; great heaths covered with Calluna vulgaris. Turf with Juniperus, Aii- 

 dromeda polifolia and Ledum palustre ; rich in Umbelliferae and Cruciferae. 

 Asia : Anabasis, Salsola, Chenopodium, Atriplex, Statice, Artemisia, Gentiana, 

 Cucubalus tatai'ica, Glycyrrhiza. America: Abietineae, Sisyrinchium, Dodeca- 

 theon, Patiaa: horridum, Ruhus odorattis, and spectabilis, Sorbus and Crataegus. 



tSoutheni hemisphere. Evergreen forests of Fa^us aiitarctica and betu- 

 loidcs, Avith Wintera aromatka. Podocarpus. Here and there, no trees 

 (Falkland Islands and east side of the Straits of Magellan), but instead, 

 shrubby growths of considerable extent of Andi-omeda, Arbutus, Empetrum, 

 and Rubus, 4-5 feet high. Extensive meadoAvs of Ag-rostis magellanica 

 and ccBspitosa, Aira flexuosa, Arena redolens and phleoides, Festuca magel- 

 lanica and erecta, Carex and Juncus. floors of Sphagnum acutifolium, 

 Avith MarcJuintia poli/morpha, Azolla magellanica, Lomaria, Callitriche 

 verna, Gunnera, Statica armeria, Galium aparine, Pinguicula alpina, 

 Lysimachia repens, Rammculus lapponicus, Caltha appendiculata and 

 sagittata, Avith Fuchsia and Sanguisorba. 



6. The Subarctic Zone. 58° — 66° of latitude. Mean temperature 

 39;^° — 43° F. ; summer temperature in the New World 665-° ; in the Old, 

 60f ° — 68°. Winter temperature of Avestern Europe 14° ; of the interior 

 of Russia 14° — 10^°. Vegetation very similar through Scandinavia, Si- 

 beria, Kamtschatka, Northern America, Iceland, and the Faroe Islands. 

 Pines, Firs, Larches, Birches, and WilloAvs predominate ; characteristic 

 growths are Cetraria islandica, Trichostom,um, lanuginosum and canescens. 

 MeadoAVS of Agrostis, Poa and Aira, Valeriana, Hieracium, atira?itiacum,, 

 Digitalis purpurea, Stachys, SAvertia, Lysimachia, Trientalis, Calluna 

 vulgaris, Erica cinerea, Bunium, Ribes, Chrysoplenium, Berberis, Hyperi- 

 cum, Prunus padua, Rosa, Trifolium. 



The South Subantarctic Zone (New Shetland) has the polar character. 



C. Frigid Zone. 



7. The Arctic Zone. This extends from the Arctic circle 66° to 72°. 

 Mean temperature 28^° — 32°, and towards the eastern and continental 

 portions far below this. This constitutes the limit of arboreal vegetation 

 and of cultivated plants. Characteristic growths common to both continents 

 are Gyrophora, Cenomyce rangiferina, Polytrichum, Aira ccBspitosa and 

 flexuosa, Pinns sylvestris and abies, Betnla nana and glandidosa, Alnus 

 glutinosa, Populus tremula, Salix, Diapensia, Cornus suecica, Azalea, 

 Andromeda, Vaccinum, Rubus chamamorus and /Sorbus auciiparia. 



48 



