SOUTH CENTRAL WING
GEOLOGY AND INVERTEBRATE PALEONTOLOGY
"Stones have been known to move and trees to speak." Shakespeare.
North of the Hall of the Age of Man of the American Museum of Natural History, containing the mastodons and mammoths, is the Hall of Geology and Invertebrate Palaeontology. At the entrance to the hall are two hemispherical forms which illustrate the six stages in the geographical development of the North American continent. The stages represented are the Upper Cambrian, Middle Devonian, Upper Triassic, Lower Cretaceous, Upper Cretaceous, Upper Oligocene. On each geology model the present outline of the North American continent has been superimposed upon that of the ancient lands and seas. They differ widely from the modern outlines in all instances except the Oligocene, which is more nearly like the present map. These models represent the first attempt at restoring the relief of the ancient lands on a curved surface.
The desk cases down the center of the hall contain the types and figured geology specimens used by James Hall, R. P. Whitfield and others in the original description and naming of species. Most of the American specimens are from New York State, although there are many from the Middle Western States. The type series, as it is designated, is arranged biologically under each period, beginning with the oldest fossiliferous period, the Cambrian, at the entrance. Geologists regard this series, with its 10,000 specimens, as the largest and most valuable collection of fossil invertebrate types in America. Toward the far end is a beautiful collection of fossil sponges from northwestern Germany.
The geological specimens in the upright cases, at the east or right-hand side, are being arranged to illustrate the development and relationship of the more common species of plants and animals of past geologic times. In the first case are striking examples of carbonization and silicification of woody fiber, ranging from Devonian to Recent in age. A large stump, with part of the roots, of a carboniferous tree from an anthracite coal mine under Scranton, Pennsylvania, is in the first alcove. Near-by are many typical fossil leaves arranged systematically.
In the remaining upright cases is a select series of fossil specimens illustrating the species of the various biologic groups of the animal kingdom. These specimens are also arranged systematically.
The specimens on the left or west side of this, the geology hall of the American Museum of Natural History, are being arranged to illustrate the order of superposition (one placed above the other) of the various beds of sedimentary rock in the earth's crust as well as the provincial distribution of the fossils and rocks during the various stages of a period. The series begins at the south (near the en-trance) with the Archozoic, which are the lowest and oldest of all rocks and contain no fossils. These are followed by the Proterozoic rocks, which contain scant remains of life. Beginning with the Cambrian period and continuing through the Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Comanchian, Cretaceous, Tertiary and Quaternary periods, life shows marked evolution and extinction in some groups and but little change in others. When it is stated that it took at least 30,000,000 years to deposit the sedimentary beds from the Cambrian to the Present and that life existed throughout this time, the length of life of man sinks into insignificance.
In three of the alcoves on the east side is the general collection of meteorites, which is one of the largest and most representative in this country, containing specimens of from 500 to 700 falls and finds that are known throughout the world. The "stone shower" that fell near Holbrook, Arizona, in 1912 and the entire mass of Ysleta, 1914, are the most striking recent acquisitions.
In another alcove, on the east side, is a desk case containing a series of rock specimens from Manhattan Island. This is arranged geographically from south to north and shows the character of the rock upon which New York City is built. In the northeast corner of the hall is a model of the Copper Queen Mine and a series of ores and other specimens from the Bisbee-Warren copper district in southern Arizona.
On the opposite or northwest corner is a display of caves and cave material, including a reproduction of part of a cave that was discovered in 1910 in mining operations at the Copper Queen Mine, and alongside is a reproduction of a chamber in Weyer's Cave, Virginia.
Conspicuous in the central portion of this section is a great mass of copper ore about three feet square by five feet high, weighing three and one half tons. It contains more than a ton of pure copper, besides some silver and gold. That portion in streaks of beautiful blue is azurite, and that in green, malachite.
Go To Next Page