DISTRIBUTION OP CONIFEROUS PLANTS. 41 



numerous, and were spread over a great part of the northern 

 hemisphere. 



The richness of the Coniferous vegetation of the Chino-Japanesc 

 region, and the prolonged existence of species whose congeners in other 

 parts of the world have long since passed away, are doubtless owing to 

 a more regular distribution of the rainfall, combined with a high 

 summer temperature. 



The North American forest region corresponds in a great measure 

 to the Europeo-Siberian forest region of the eastern hemisphere. 

 "A broad forest zone passes through the whole continent from 

 Behring's Straits to Newfoundland, and southwards as far as Florida 

 and the mouths of the Mississippi." * The northern belt includes 

 the zone of Abies nigra and A. alia, intermixed in the eastern 

 portion with the Scrub, Yellow, and "White Pines (Pinus Banksiana 

 P. imps, P. mitis, and P. Strobus). Further south the Coniferous 

 trees are mixed with broad-leaved deciduous trees, but the mountain 

 sides and many parts of the lower grounds are covered with forests 

 of Pine and Fir. In the swampy district that extends from New 

 Jersey southwards, and along the river banks of the South Eastern 

 States, the Deciduous Cypress and White Cedar are abundant; and 

 an immense tract called the "Pine Barrens," extending for hundreds 

 of miles along the Atlantic coast, is covered with Pinus australis 

 and P. tceda. 



The Californian and Mexican region. The maximum of Coniferous 

 vegetation in North America is reached in the long strip of territory 

 lying between the Kocky Mountains and the Pacific Ocean, and 

 extending from British Columbia to beyond the Mexican line. In 

 this region not only is the area covered by Coniferous forests very 

 great in proportion to the entire extent, but also the trees of most 

 of the species attain so gigantic a size, that all other kinds met 

 with in other parts of the world, with the exception perhaps of the 

 Indian Deodar, may be called dwarf in comparison. The number 

 of species in this region, especially of Firs and Pines, is exceptionally 

 great ; the Cypress tribe is represented by many species; the Yew 

 tribe by at least two; and California is well known to be the home 

 of the gigantic Wellingtonia and Eedwood. 



The Coniferous forests of California are continued in the highlands, 



* Thomd's Structural Botany, p. 446i 



