1 306 A USTRALASIA~ ILL USTRA TED. 



small isolated settlements,- the present disunited colonial elements are gradually being 

 weldrd. Then, the geology of Australia teaches a lesson not only of high scientific 

 interest, but one of great commercial significance, namely : that the formations afford 

 evidence of an enormous area of soils adapted for agricultural and pastoral purposes, and 

 also of the rocks that indicate rich mineral resources. In these we have assurance of the 

 future occupation of Australia by a vast industrial population. 



On reference to a geological map of Australia, it will be seen that the features of 

 the coast-districts, as well as of considerable portions of the interior, have been more or 

 less definitely ascertained. But a large extent of the interior has not yet been examined. 

 Nevertheless, from the explorations already made, we learn that it is not a worthless 

 desert that the rocky slate and granite hills, which were at first traversed with such diffi- 

 culty by the explorers, show the existence of the great metalliferous formations ; and that 

 the wide-spreading stony downs, so deficient in permanent surface-water, indicate the 

 enormous area of artesian water-bearing strata. And it will further be seen that we have 

 formations of igneous and sedimentary origin representative of most of the principal epochs 

 of the earth's history, as recorded in the well-investigated lands of the Northern Hemi- 

 sphere. And what we find here, in regard to the fossil contents of the rocks, corrobo- 

 rates observations made elsewhere, that, the farther we go back into the past, the more 

 universal and uniform were the life-conditions of the earth. Thus, the more ancient 

 formations of Australia yield fossils of species identical with those found in strata of the 

 same age in other parts of the globe ; we may, therefore, infer that in the earliest 

 epochs certain forms of life were unlimited in their range, and that as the surface of the 

 globe became in places more and more altered by physical changes old lands sinking 

 beneath the ocean and new ones rising from it so the ancient types of life gradually modi- 

 fied in adaptation to their altered environment, and thus the progressive differentiation 

 resulted in the varied animals and plants that we find now living in the different regions 

 most suited to them. 



In portions of the globe, such as Britain, where geological changes have been frequent, 

 it might naturally be inferred, as we find it to be the case, that corresponding changes in 

 the animal and vegetable life would be so marked as to lead to the belief that old races 

 had suddenly disappeared and given place to others quite distinct. But in other 

 portions where the old land-surfaces have remained during long periods, modified only by 

 slight physical changes, we should expect the persistence of the ancient types of life, not 

 only upon the land, but in the surrounding ocean. And such we find in Australasia, 

 which, on this account possessing surviving ancient forms of life long since extinct else- 

 where affords one of the most interesting and important regions of the globe for investi- 

 gation in various branches of science. The botanist and zoologist would be at a loss to 

 account for the origin of the living flora and fauna peculiar to Australia, did not the 

 palaeontologist and geologist come to their aid with the "testimony of the rocks." 



A few years ago, a small pine, Pkerosphoera Fitzgcraldi (F. v. Mueller), was found 

 growing in a moist and cool shady place in one of the precipitous ravines of the Blue 

 Mountains, near Katoomba ; its nearest living relative, the " Huon Pine," now occupies 

 the cooler region of Tasmania ; and geological evidence points to the conclusion that the 

 little Blue Mountain pine, owing to its damp secluded retreat, has survived from the 



