440 LAND ANIMALS 



and Siberia one finds lynxes, wolves, foxes, martens, gluttons, weasels, 

 minks, and badgers. The Asiatic tiger contrasts with the American 

 puma, and the wildcat of Europe has no close relative in America. 

 The skunk is absent from Europe. Siberia has its wild dog, Cyon, 

 and a brown in place of the American black bear; in addition there 

 is the American grizzly bear in the western region of North America. 



The absence or scarcity of snakes makes for safety for birds, as 

 does the absence of monkeys and other arboreal tropical mammals. 

 The weasels, however, take a heavy toll. Among the birds especially 

 abundant in the northern coniferous forests are the grouse, the gros- 

 beaks and crossbills, woodpeckers, nutcrackers, jays, and their allies, 

 with a host of migrants of other groups in the nesting season. Green 

 woodpeckers are characteristic of the woods of the Old World, while 

 spotted ones occur in both Old and New World forests. 



The Amphibia are represented by a few Hylidae, which are more 

 numerous in America ; in Eurasia they barely reach the coniferous belt. 

 True frogs (Rana) range into the taiga in both hemispheres. 



The insect life is rich. In Asia wild bees reach the Arctic Circle; 

 in America they penetrate only into the southern part of this forest. 

 Conifers are much more vulnerable to insect attacks than are beeches 

 and maples. Repeated complete defoliation is fatal. Beetles are im- 

 portant pests from the viewpoint of the forester. Burrowing bark beetles 

 are killed in healthy trunks by the rise of sap, but after repeated 

 attacks, aided perhaps by injuries due to wind, snow, and ice, the 

 beetles may establish themselves and kill many trees. 53 Wood wasps, 

 Sirex gigas, pine sawflies, Lophyrus pini, pine geometrids, pine pro- 

 cessionary caterpillars, Cnethocampa, and others, often attack in 

 masses with severe results. Termites, the pests of the tropics, are 

 absent. 



Animals of the northern coniferous forests exhibit two types of 

 migration. In the spring comes the great northward migration of birds 

 which nest in the north woods, and in the winter there is the great 

 southward migration of caribou, arctic hares, and to some extent, of 

 arctic birds, which overwinter in the forest. 



This northern coniferous forest is the great fur-producing region 

 of the world. 54 The finest of the furs come from the north where dense 

 furs are produced as a protection from cold, from near fresh water 

 which gives a sheen to the fur, finally from wooded areas which 

 protect the luster from being faded by sunlight. Otter, weasel or 

 ermine, mink, marten, fisher, sable, and wolverine, belonging to the 

 family Mustelidae, supply the finest of all furs; and the staple supply, 

 of only slightly less fine quality, is afforded by the beaver and musk- 





