SCHMIDT: ANIMAL GEOGRAPHY 769 



Darwin had been strongly influenced in his whole evolutionary trend by the 

 facts of animal and plant distribution. He devotes two chapters in the Origin 

 of Species to this subject, and in these he discusses the genetic similarities within 

 the faunas and floras of the several continents; the means of dispersal available 

 to plants and animals; the influence of glacial periods on distribution; the distri- 

 bution of freshwater animals; and the inhabitants of oceanic islands. In illustra- 

 tion of the last mentioned topic he deals especially with the animals and plants 

 of the Galapagos Islands, where the phenomena of insular distribution had so 

 greatly impressed him in 1835. 



Alfred Russell Wallace, Darwin's friend and fellow evolutionist, had lived 

 for many years in tropical regions, first in the Amazon Basin and later in the 

 East Indies, where he had been especially impressed by the phenomena of animal 

 distribution. He thus had a broader and more direct and intimate acquaintance 

 with the subject than any other naturalist traveler of his century. He was con- 

 tinually at work on this subject from 1860 until 1876, the date of publication of 

 his two volumes on The Geographical Distribution of Animals. He somewhat 

 modestly refers to this work as an extension and amplification of the two chapters 

 on the subject in the Origin of Species, comparing it with Darwin's own two- 

 volume expansion of the chapters on animals and plants under domestication. 

 The two principal sections of Wallace's work are contrasted as "zoological geog- 

 raphy," a descriptive discussion of the land animals of the different zoogeographic 

 regions, and "geographical zoology," a review of the distribution of vertebrates 

 and certain invertebrates, group by group. This work was ponderous and at the 

 same time naive in supposing that "a solution of zoogeographic problems could 

 be attempted with some prospect of success." It remains a necessary work to a 

 specialist in this subject, but modern changes in classification, the great advances 

 in paleontology, and the rise of ecology, combine to make it useless as an intro- 

 duction to animal geography. The more popularly written Island Life (1880) is 



Figure 1. General map of the geographic distribution of animals, drawn up by Ludwig 

 K. Schmarda, 1852. The land realms are: I. the Arctic, realm of fur bearers and aquatic 

 birds; II. Central Europe, realm of insectivores and staphilinid and carabid beetles; 

 III. Caspian Steppe, realm of the saiga antelope and of burrowing rodents; IV. Central 

 Asian Steppes, realm of the horse tribe; V. European Mediterranean, realm of heteromeran 

 beetles; VI. China, realm of pheasants; VII. Japan, realm of the giant salamander; 

 VIII. North America, realm of rodents, conirostrine and dentirostrine birds; IX. Sahara 

 Desert, realm of the ostrich and of melasomas (tenebrionids) ; X. West Africa, realm of 

 catarrhine monkeys and termites ; XI. Highland Africa, realm of ruminants and pachy- 

 derms; XII. Madagascar, realm of lemurs; XIII. India, realm of carnivores and pigeons; 

 XIV, the Sunda World, realm of snakes and bats; XV. Australia, realm of the marsupials, 

 monotremes and meliphagid birds; XVI. Central America, realm of land crabs; XVII. 

 Brazil, realm of edentates and platyrhine monkeys; XVIII. Andean, realm of the llama 

 and condor; XIX. Pampa, realm of the viscacha and "harpalid" beetles; XX. Patagonia, 

 realm of Darwin's rhea and of the guanaco; XXI: Polynesia, realm of nymphalid butter- 

 flies and of the Apteryx (New Zealand). The marine realms are: XXII. Arctic Ocean, 

 realm of marine mammals and amphipod crustaceans; XXIII. Antarctic Ocean, realm of 

 marine mammals and penguins; XXIV. North Atlantic Ocean, realm of cods and herrings; 

 XXV. South European Mediterranean, realm of the labrid fishes; XXVI. North Pacific 

 Ocean, realm of the scombrid and mail-cheeked fishes; XXVII, Tropical Atlantic Ocean, 

 realm of plectognath fishes, manatees, and of pteropods; XXVIII, Indian Ocean, realm of 

 buccinoids and hydroids; XXIX. Tropical Pacific Ocean, realm of corals and holothurians; 

 XXX. South Atlantic Ocean; XXXI. South Pacific Ocean. 



