ESTUARINE FACIES embraces the deposits faunas of lagoons and estuaries. The sediments are usually irregularly bedded muddy said,, and clays. Here is found a commingling of brackish water types with marine organisms, fresh-water and terrestrial types. A fine example of Snell an estuarine facies, is afforded by the Lower Car boniferous nodnle-bearing shales of :\lazon Creek, near Morris, Ill.. described by Meek and Wor then. Seader, and others. The nodules have furnished a very large congeries of plants and animals. There are represented her ferns. am phildans. fish. insects, spiders, scorpions, myria pods. eurypterids, crustaceans. aquatic• worms, la inellibranehs of marine and fresh-water types. of fresh-water. marine. and terrestrial types. No strictly marine types, like erinoids and brachiopods, occur here, those present being spe cie: x% hieh could live in brackish water. Other examples of estuarine facies are found in the Ca rhoni ferous, Mesozoic, a nil 'Tertiary formations of Europe. In all probability many of the coal measure swamps were of estuarnie nature, for section: through the beds show alternations of marine and fresh or brackish water faunas, VnEsn-W.ITEn FAcws appears first in the Cal boniferous in the form of swamp deposits, now turned into coal. In these deposit, are alanidant fossil plaids of various types, and remains of fresh-water mollusks, insects, etc., and also of am phibian: and lisp. In the Mesozoic, and in more pronounced degree in the Tertiary. lacust rine de
posits are largely developed. They may be rec ognized by their contained fresh-water shells: Palndina, Goniobasis, PI:worlds Limna.a, Unit). and Ainalonta. They have afford,d also the far more important and more interesting vertebrate remains, such as the dinosaurs, birds, and mam mals. Terrestrial facies, represented by deposit.: of flood plain. desert, and prairie, do not as a rule afford many fossil remains. The loess. a re cent accumulation of dust and river mud. con tains land and fresh-water shell:: :ail the White 'River Miocene clays of Colorado, containing fine ly preserved vertebrates. are thought to have been aecumulated largely as dust upon a Tertiary prairie.
t'omPOSITE FACIES. The fossil (dements of a fauna may be distinguished as antochthonons, or those which naturally belong in the deposits where found and which hove been buried where they lived or where they fell to the bottom; and heterochthonous. or those which (me their en tombment to the agencies of or other means of transportation, and have been buried far from their natural habitats. The autoch thnnou: fossils are the more reliable for 7.01:1 1 correlation, while the heterochtlionous fossils in dicate the nature of prei;xistent faunas and the proximity of neighboring faunas I if different facies. •