Frederick Chapman

“ Among these are the fact that our knowledge of the life forms of a given geological period is necessarily incomplete, that the differences in the fossil contents of rocks may depend not only on differences of age but also in the conditions under which the organisms lived and the rocks were accumulated, and that forms of life originating in one area do not spread themselves immediately over the earth but migrate at velocities depending on their mode of life and the presence or absence of barriers to their progress. ”

“ The broad generalizations that rocks may be identified by their fossil contents and that the testimony of the rocks demonstrates the general order of evolution from simple to complex forms, have only been placed on a surer footing by long continued investigations. The modifications produced by conditions of deposit, of climate and of natural barriers to migration, while introducing complexities into the problems of Palaeontology, are every year becoming better known ”

“ CIRRIPEDIA OR BARNACLES.—These curious modifications of the higher group of Crustacea (Eucrustacea) date back to Ordovician times. They appear to have tried every possible condition of existence; and although they are mostly of shallow water habits, some are found at the great depth of 2,000 fathoms (over two miles) . Those which secrete lime or have calcareous shells, attach themselves to stones, pieces of wood, shell-fish, crabs, corals and sea-weeds. Others are found embedded in the thick skin of whales and dolphins, or in cavities which they have bored in corals or shells of molluscs. ”

“ Those of us who are accustomed to take the field, armed with a hammer, in the search for “medals of creation” and from time to time have experienced the sporting enjoyment of bringing to light a rare or perfect specimen are quite prepared to support his claim. But the student of fossils needs the help of a text book to guide him to the literature on the subject, to help him with his identifications or to indicate that some of his finds are new and hitherto undescribed. ”

“ As regards the places most suitable for collecting fossils, the Cainozoic beds are perhaps, the most accessible to a beginner, especially in Victoria. For instance, the cliff exposures at Beaumaris, Port Phillip, will afford a plentiful supply of the little heart-shaped sea-urchin, Lovenia, and an occasional Trigonia and Limopsis, as well as many other fossils of the great group of the shell-fish or mollusca. The richest bed containing the sharks’ teeth at the above locality is almost perpetually covered with a bed of shingle, but can be reached by digging at the cliff-base. ”

“ Sponges are either fixed or lie loosely on the sea-floor. They possess no organs of locomotion, and have no distinct axis or lateral appendages. They exist by setting up currents in the water whereby the latter is circulated through the system, carrying with it numerous food particles, their tissues being at the same time oxygenated. Their framework, in the siliceous and calcareous sponges, is strengthened by a mineral skeleton, wholly or partially capable of preservation as a fossil. ”

“ The order Carnivora is represented in Australia by the Native Dog or Dingo (Canis dingo) . It is by no means a settled question whether the Dingo can boast of very great antiquity. The evidence of its remains having been found under volcanic tuff beds in Victoria is not very convincing, for the original record does not indicate the precise position where the bones were found. The fact of the remains of the Dingo having been found in Cave deposits often associated with extinct marsupials, goes a good way to prove its antiquity. ”

“ For instance, among the group of the graptolites, in Britain the genus Bryograptus occurs only in the Upper Cambrian and the genus Leptograptus only in the Upper Ordovician rocks. In Victoria these two genera, together with typical Lower Ordovician forms, may be found near Lancefield preserved on a single slab of shale. In the same way, in a single quarry in Triassic rocks in New South Wales, a number of fossil fish have been found and described, some of which have been compared to Jurassic, others to Permian, and others to Carboniferous forms in the Northern Hemisphere. ”

“ The Graptolites were so named by Linnaeus from their resemblances to writing on the slates in which their compressed remains are found. They form a very important group of Palaeozoic fossils in all parts of the world where these rocks occur, and are well represented in Australasia. The species of the various Graptolite genera are often restricted to particular beds, and hence they are of great value as indicators of certain horizons or layers in the black, grey or variously coloured slates and shales of Lower Ordovician to Silurian times. ”

“ Australia has in the past been peopled by two distinct types of man. (1) , the ancestors of the Tasmanians, now alas, extinct, who according to some authorities came by way of Australia from Papua through the Malay Peninsula, passing over to Tasmania from the mainland before the separation caused by the subsidence of the Bass Strait area; and who were represented by a negroid or woolly-haired type: (2) , the present aboriginals of Australia, showing affinities with the Dravidians of Southern India, a primitive race from whose original stock the white Caucasian races of Europe were derived. ”

“ The shells are sometimes associated with leaves and other vegetable remains, if forming part of an alternating series of freshwater and marine conditions. An example of this type of sediments is seen in the Mornington beds of the Balcombian series in Victoria.
MUDSTONE is a term applied to a hardened clay deposit derived from the alteration of an impure limestone, and is more often found in the older series of rocks. Mudstones are frequently crowded with fossils, but owing to chemical changes within the rock, the calcareous organisms are as a rule represented by casts and moulds. ”

“ In the distribution of marine animals at the present day we find that organisms of simple structure are generally more wide-spread and less susceptible to changes in their environment than are the more complex organisms with specialised structures. Hence we find, for instance, a fossil species of the « 17 » Foraminifera may persist unchanged through several geological periods, while a species of fossil fish has in general not only a short range in time but often a restricted geographical extent. ”

“ Almost all the records of Australian human remains that have been found in other than ordinary burial places, have proved to be of comparatively recent date. For example, the partially lime-encrusted body found in the cave in the Mosquito Plains, north of Penola, South Australia, recorded by Tenison Woods, is that of an aborigine who, in the early days of settlement, crawled into the cave in a wounded condition. Other occurrences of human remains in caves, but of fairly recent date are, a child’s skull found in a small cave at Bungonia, Co. Argyle, New South Wales, recorded by Etheridge ”

“ Polyzoa are very abundant in the Cainozoic beds of Australia, New Zealand, and elsewhere (Fig. 25) . In the Mesozoic series, on the other hand, they are not so well represented; but in Europe and North America they play an important part in forming the Cretaceous and some Jurassic strata by the abundance of their remains.
WORMS (VERMES) .—The hard, calcareous tubes of Sea-worms, the Polychaeta (“many bristles”) are often found in fossiliferous deposits, and sometimes form large masses, due to their gregarious habits of life ”

“ The Victorian mudstone at Heathcote may be of Ordovician age or even older; it has afforded a limited fauna of brachiopods and trilobites, amongst the former being various species of Orthis, Chonetes, and Siphonotreta. The latter genus is represented in both the Lower and Upper Ordovician rocks of slaty character in Victoria (Fig. 85 B) .
Silurian Brachiopods.—
The Silurian system in Australasia as in Europe, N. America and elsewhere, is very rich in brachiopod life. It is impossible to enumerate even all the genera in a limited work like the present, the most typical only being mentioned. ”

“ When shale occurs between the coal-layers it is spoken of as the under-clay, which in most cases is the ancient sub-soil related to the coal-layer immediately above. It is in the shales that the best examples of fossil ferns and other plant-remains are often found. The coal itself is composed of a partially decomposed mass of vegetation which has become hardened and bedded by pressure and gradual drying. ”

“ Flint is distinguished from chert by its being black in the mass, often with a white crust, and translucent in thin flakes; chert being more or less granular in texture and sub-opaque in the mass. Both kinds appear to be formed as a pseudomorph or replacement of a portion of the limestone stratum by silica, probably introduced in solution as a soluble alkaline silicate. Both flint and chert often contain fossil shells and other organic remains, such as radiolaria and sponge-spicules, which can be easily seen with a lens in thin flakes struck off by the hammer. ”

“ Attention should also be paid to the conditions under which the deposits accumulated, since it is clear that rocks may be formed at the same time in different areas and yet contain many distinct fossils by reason of climatic or bathymetrical differences. Among living marine organisms we find certain forms restricted to sandy or muddy sea-bottoms and others « 18 » to clear water, and these changes in the conditions of deposition of sediment have played their part in past geological periods in determining differences in the fossil faunas of rocks which were laid down simultaneously. ”

“ The only true Carboniferous marine fauna occurring in Australia, appears to be that of the Star Beds in Queensland, but so far no corals have been found. « 117 » The so-called Carboniferous of Western Australia may be regarded as Carbopermian or even of Permian age. The marine Carbopermian beds of New South Wales contain several genera of Corals belonging to the group Rugosa, as Zaphrentis (Fig. 70 D) , Lophophyllum, and Campophyllum. ”

“ The Diprotodon-breccias of Queensland have afforded several species of Helix and other land-shells, as well as the brackish-water genus Melania. The Raised Beaches of Queensland, New South Wales, Victoria, and Tasmania all contain species of land and freshwater shells identical with those now found living in the same localities.
The Raised Beaches of New Zealand contain numerous marine shells all having living representatives. Some of these elevated beaches occur as high as 150 feet above sea-level at Taranaki, and at 200 feet near Cape Palliser in Cook Strait. ”

“ Torlessia is found in the Trias or Lower Jurassic of the province of Canterbury, New Zealand (Fig. 82 D) . The genus Serpula is widely distributed, occurring in the Carbopermian (Upper Jurassic Series) , near East Maitland, New South Wales (S. testatrix) , in the Jurassic of W. Australia (S. conformis) , in the Lower Cretaceous of Wollumbilla, Queensland (S. intestinalis) , and the Darling River, north west of New South Wales, (S. subtrachinus) , as well as in Cainozoic deposits in Victoria (S. ouyenensis) . Ditrupa is very abundant in some shelly deposits of Janjukian age in Victoria. ”

“ Seeing the difficulties in the way of discovering reliable occurrences of man’s handiwork in isolated examples amongst the older superficial deposits of silt and gravels, the ancient sand-dunes of Victoria, which date back at least to Upper Pliocene, should afford favourable conditions for the preservation of any really ancient kitchen middens, did such exist. ”

“ They are sometimes placed in a class by themselves (AGNATHA) . The orders of this primitive fish series as represented in Australasia are the Osteostraci (“bony shells”) , of which the remains of the Cephalaspis-like head-shield of Thyestes has been found in the Silurian of N.E. Gippsland, Victoria (Fig. 122) ; and the Antiarchi, with its many-plated cuirass, armoured body-appendages, internal bony tissue, and coarsely tuberculated exterior, as seen in Asterolepis australis, a fossil occasionally found in the Middle Devonian Limestone of Buchan, Gippsland. ”

“ The Lower Carboniferous sandstone of Burnt Creek and other localities near Mansfield, Victoria, contains an abundant fish fauna, associated with stems of Lepidodendron. The slabs of sandstone are often ripple-marked and show signs of tracks and castings of shore-living animals. These deposits were probably laid down in shallow water at the shore margin or in salt lagoons or brackish areas skirting the coast, into which at intervals the remains of the giant lycopods were drifted. ”

“ Trilobites, as a group, seem to have adapted themselves to almost all conditions of marine life: « 223 » some are found in the hardened black mud of shallow waters, whilst others are to be looked for in the limestones and excessively fine sediments of deeper waters. In all probability certain of these forms crawled over the soft, oozy sea-bed in order to obtain their food, and consequently their remains in the stratified rocks would be restricted to the fine black shales; whilst the freely swimming forms could change their habitat at will, and would be found alike in sandy or clayey deposits. ”

“ As a general rule the various types of animals and plants become simpler in organisation as we descend the geological scale. For example, in the oldest rocks the animals are confined to the groups of Foraminifera, Sponges, Corals, Graptolites, Shell-fish and Trilobites, all back-boneless animals: whilst it was not until the Devonian period that the primitive fishes appeared as a well-defined group ”

“ It is reasonable to infer that tooth and scale belong to the same species; and in view of the close relationship of the tooth with that of the living mudfish, rather than with that of the Ceratodus found fossil in the Mesozoic of Europe, it may be referred to Neoceratodus, in which genus the living species is now placed.
Fig. 127—Scale of Ceratodus (Neoceratodus) (?) avus, A. S. Woodw.
Jurassic. Kirrak, S. Gippsland, Victoria. About nat. size
« 266 »
Fig. ”

“ A few doubtful remains of this group occur in Australia.
The bud-shaped echinoderms (Blastoidea) also occur chiefly in Devonian and Carboniferous strata. This is also a rare group, and is represented by several forms found only in New South Wales and Queensland.
The well known and beautiful fossil forms, the Stone-lilies (Crinoidea) have a very extended geological history, beginning in the Cambrian; whilst a few species are living in the ocean at the present day. ”