(4) The region of the beautiful Pinus canariensis, extending to the height of 6400 ft.; here the broad-leaved trees have ceased to grow, but arborescent heaths are found throughout its whole extent, and specimens of Juniperus oxycedrus may be met with.
The chief trees of the country are the aspen (Populus tremuloides), the ash-leaved maple (Negundo aceroides), oak (Quercus alba), elm (Ulmus Americana), and many varieties of willow.
The cut-leaved oaks are represented in eastern Asia by several species, of which Q.
The remains of palms (Sabctl and Nipa) as well as of other large-leaved Monocotyledons are preserved.
Or to take the small but welldefined group of five-leaved pines, all the species of which may be seen growing side by side at Kew under identical conditions: we have the Weymouth pine (Pinus Strobus) in eastern North America, P. monlicola and the sugar pine (P. Lambertiana) in California, P. Ayacahwite in Mexico, the Arolla pine (P. Cembra) in Switzerland and Siberia, P. Peuce in Greece, the Bhotan pine (P. excelsa) in the Himalayas, and two other species in Japan.