8

THE CONIEEIUE.

Kamtschatka and Dauria. It is probably also thisspecies which in European Russia extends from theDwina to the White Sea , since our larch is not elsewherefound in Russia . In North America , where the arborealvegetation in general, ceases at a lower latitude, thelimit of the Coniferas is placed towards the west onthe Mackenzie, between 67° N. and 68° N., at whichpoint Abies alba and ( Larice ) microcarpa still appear, butfor the last time; whilst towards the east, in the countryabout Hudson’s Bay, they disappear much earlier ; evenbelow 60° N. in Labrador. It may thus be assumedthat the northern limit of the Con if era! is, in general,placed between 68° and 70° N., receding only on theAtlantic coasts of North America to 00° and 58°. To-wards the south, the range of some species extends tothe extremity of the continents; thus Podocarpus alpina(R. Br.) occurs even at 45° S. in Van Diemen’s Land,and Juniperus uvifera (Don) at Cape Horn (55° and56° S.)

In the lowlands of the tropical regions, especiallynorth of the equator, the distribution of this familyappears to be interrupted, for in these regions the fewspecies which do occur are confined to the high moun-tains, as for instance, Podocarpus and Dammara in theMoluccas . It appears indeed that generally, even at30° N. no species is any longer found in the lowlands,nor except at an elevation of at least 2000 feet abovethe sea. The altitude at which some species willflourish, naturally depends also upon the latitude of theplace. In the East Indies, P. longifolia occurs, in thelatitude of 28° N. at an altitude of between 2000 and0000 feet, whilst P. Gerardiana on the Sutlej , makes itsfirst appearance between 5000 and 10,000 feet; AbiesKlmtrow in Gurwhal and Bissehur, between 7000 and10,000, and A. Pindrow at an elevation of from 10,000to 12,000 feet.

In the mountains of Mexico , according to Galeotti,(Bullet, de l’Acad. de Bruxelles, vol. X, No. 2,) some