Forests (Cmiliniicd) 



species of birds in, 307 

 species of mammals m, 307 

 biomasses of birds in, 135 

 breeding season in and photopenod 



and temperature, 299 

 climax, equilibrium in decompo- 

 sition of leaves and reabsorp- 



tion of nutrients in, 165 

 confining of certain species of 



birds to either deciduous or 



coniferous on basis of behavior 



patterns alone, 250 

 coniferous: 

 and formation of podzolic soils, 



172 

 changes in range of species of 



as hastened by man, 308 

 climate of, 301-302 

 comparison of to deciduous, 308 

 description of, 301 

 destructive insects in, 309-310 

 dispersal of isolated fauna in 



during interglacial periods, 30fi 

 distribution of, 301 

 feeding habits of mammals in, 



308-309 

 habits of perennial animals that 



remain active over winter in, 



309. 

 isolation of animals during 



glaciation into four refugia of, 



308 

 isolation of birds during glacia- 

 tion in four refugia of, 308 

 migration in, 309 

 northward dispersal of in thermal 



maximum period, 317 

 occurrence of mor humus in, 171 

 origin of, 301 

 plant associations of, 302 

 populations of invertebrates in, 



310 

 refugia for survival of during 



Pleistocene era in North 



America, 286 

 retention of foliage in, 121 

 separation of during Tertiary 



era into North American and 



Eurasian biociations, 307 

 uniform animal composition of 



during early Tertiary era, 307 

 use of by man, 308 

 cryptozoa in, 134 

 decaying logs and stumps of as 



habitats for soil animals, 134- 



135 

 decomposition of dead leaves in, 



121 

 dry weight of ground Utter in, 165 

 effects of browsing on trees and 



shrubs in, 177 



Forests (Conlinuctl) 

 European deciduous: 

 as descended from Arcto- tertiary 



forests, 298-299 

 birds m, 299 

 mammals in, 299 

 similarity in genera of plants and 

 animals of to North American 

 species, 298-299 

 fertility of as factor in breeding- 

 bird populations, 135 

 foliage arthropods in, 135 

 footspan of birds and choice of 

 coniferous or deciduous, 248- 

 249 

 general similarity of niches and 

 microhabitats in different types 

 of, 137-138 

 growth of: 

 during climatic optimum in North 



America, 289-290 

 during post- Pleistocene era, 289 

 during sub-Atlantic period of 



North America, 291 

 during xerothermic climatic 

 period in North America, 290- 

 291 

 hearing and voices of animals in, 



299 

 inability of some species to occupy 

 both coniferous and deciduous, 

 138 

 inability of to support large grazing 



populations, 328 

 influence of humus of on species of 



soil animals present in, 138 

 life- history of millipede in, 143- 



144 

 light intensities in; 

 during summer, 122 

 vertical gradients in, 123 

 logging in, 138 

 measuring annual woody increment 



of trees of, 204 

 mineral content of leaf fall in, 165 

 modifications of and wildlife of by 



man, 300 

 non- breeding bird population in, 



135 

 North American coniferous: 

 boreal and western biociations 

 of as enhanced by Pleistocene 

 glaciation, 308 

 boreal, compression of into 

 Appalachian refugium, 308 

 origins of breeding bird species 

 in boreal and western compared, 

 308 

 species of birds in, 302-303 

 species of mammals in, 302-303 

 western, tripartite segregation of. 



Forests (Coiilimied) 

 North American temperate 



deciduous: 

 buds in biociation of, 295-296 

 humidity in, 293 

 invertebrates in biociation of, 



296-297 

 location of biociation in, 95 

 plant associations of, 295 

 mammals in biociation of, 295- 



296 

 occurrence of biociation in 



climax and late serai stages of, 



295 

 precipitation in, 293 

 reptiles and amphibians in 



biociation of, 296-297 

 temperatures in, 293 

 of North America during Pleisto- 

 cene era, 285-286 

 outbreaks of spruce budworm in, 



230 

 population densities in and 



luxuriance of vegetation of, 138 

 ratio in numbers of individuals per 



hectare between different animal 



groups of, 130 

 relative humidity of compared to 



grassland and forest- edge, 121 

 seasonal changes in: 

 and effect on mammal popula- 

 tions, 137 

 during vernal aspect, 13 7 

 hibernation and, 137 

 migration of birds and, 137 

 population of soil macrofauna 



during hiemal aspect of, 13? 

 serai, organic content of floor of, 



165 

 soil of: 

 characteristics of animals in, 



131-132 

 density of animals in, 130 

 species of animals in, 130, 132- 



134, 134 

 vertebrates as part of fauna of, 



135 

 virgin abundance of soil animals 



in, 130 

 water in as habitat for organisms, 



130-131 

 southeastern North American: 

 birds in, 298 

 dispersal of animal species into 



deciduous forest and forest- 

 edge communities, 298 

 mammals in, 298 

 occurrence of subspecies of 



northern animals in, 298 

 reptiles and amphibians in, 298 



Index 419 



