460 NATURAL SCIENCE. Dec, 



mammalia are almost exclusively marsupial, the only other represen- 

 tatives of the group now living being the opossums of America. Of 

 the birds, there are no familiar types, as vultures, pheasants, and 

 woodpeckers, but such peculiar forms as honeysuckers, paradise 

 birds, lyre birds, and cassowaries. The snakes and lizards, though 

 numerous, are also singular. 



In the plants the same peculiarities are to be seen. The Malayan 

 flora is a special development of that which prevails from the Hima- 

 laya to the Malay Peninsula and South China. Further east, this 

 flora intermingles with that of Australia and Polynesia. The 

 Australian flora is highly peculiar, and very rich in species ; while 

 that of New Zealand is poor but very isolated. Special sketches of 

 both faunas and floras are given in connection with each colony. 



The geological relations of this portion of the world are undoubtedly 

 with Asia. Dr. Wallace thinks that the exceedingly shallow seas 

 connecting the islands of the northern area show that not only Java 

 and Borneo, but even the Philippines formed a south-eastern extension 

 of the Asiatic Continent in a comparatively recent period. The 

 vegetable and animal life shows this still more clearly. But between 

 this mass and that of New Guinea and Australia, we pass over deep 

 seas and find ourselves among a set of animals for the most part 

 totally unlike those of the Asiatic Continent, or any other part of the 

 globe. The resemblances of these southern life-forms to the fauna of 

 Europe during the Secondary period are very striking, and lead Dr. 

 Wallace to say that it is generally believed that the countries they 

 now inhabit have been almost completely isolated from other land- 

 masses since the Oolitic period. The evidence derived from a study of 

 New Guinea, the Moluccas, and the islands as far as Lombok in the 

 north, and Tasmania in the south, goes to prove that Australia was 

 formerly more extensive than it is at present. That this is clear as 

 regards its eastern seaboard is proved by the Great Barrier Reef, 

 whose coral walls still indicate the former limits of the coast-line in 

 this direction. On the same coast, but further removed from the 

 mainland, are some scattered islands, conspicuous among which is 

 New Caledonia, and this is slowly sinking. 



Australia must, therefore, says Dr. Wallace, be regarded as an 

 ancient continent of the Secondary or early Tertiary period now 

 gradually diminishing, and this phenomenon of subsidence is displayed 

 in New Caledonia and in some other islands of the South Pacific 

 Ocean. Dr. Wallace is careful to point out that it is now recognised 

 that coral islands do not prove subsidence wherever they occur, but 

 may, and frequently do, indicate areas of elevation at a recent period. 



Passing now to the special chapters of the book, we find the 

 present volume confined to two great divisions, (i) Australia, in- 

 cluding Tasmania, and (2) the New Zealand group. Malaysia, 

 Melanesia, Polynesia, and Micronesia will form the subject of Dr. 

 Wallace's second volume. 



Australia itself, as a whole, is first dealt with, subsequent chapters 

 treating in turn of New South Wales, Victoria, South Australia, 

 West Australia, Queensland, and Tasmania. 



With regard to Australia as a whole, Dr. Wallace calls attention 

 to the simple conformation of the land-mass, which rises generally 

 from the coasts into elevated uplands in the interior. But the 

 assumption that Australia forms a vast table-land, with elevated 

 borders sloping towards the interior, must be taken with considerable 

 qualification. The Australian highlands form no connected whole, 



