Includes Supplementary Information.

It is particularly fitting that the University of Nebraska State Museum should at this time, on the completion of fifty years of active field work, be chosen as host institution for the first field conference of the newly-formed Society of Vertebrate Paleontology. The Society thus honors not only the Museum and the University of Nebraska but also pays tribute to the accomplishments of Professor Erwin H. Barbour, who has just completed fifty years as Director of the Museum. To Professor Barbour, leader in paleontological research in Nebraska, this guide is respectfully dedicated.

It is not the purpose of this guide to repeat or even to summarize to any extent what has already been written concerning the Tertiary and Pleistocene stratigraphy and paleontology of Nebraska. The method of treatment is rather to focus attention on the local stratigraphy and faunal relationships at important locations within the State and to draw attention to places where the evidence for certain conclusions is good and where it appears to be weak or unsubstantiated. When one becomes familiar with the variable lithology and known successions at critical sections, a regional concept begins to form. This is decidedly important in understanding the processes which have played a part in the geomorphologic development of the Great Plains and furnishes a background for comprehending the slow but progressive changes in the animal life.

A generalized classification of the Tertiary deposits of Nebraska is given in Table 1, and the Pleistocene classification is shown in Table 2. Both of these have undergone numerous changes in the last few years, but it is believed that the general stratigraphic relationships are now fairly well understood although much remains to be done to clarify the details of the regional picture.

The Tertiary sequence in Nebraska may best be explained as being composed of four groups, or sedimentary “cycles,” beginning with the lower Oligocene. These are (1) the White River Group, (2) the Arikaree Group, (3) the Hemingford Group, and (4) the Ogallala Grqup (see Lugn, 1939B). The Pleistocene sequence is more complex.

The investigation leads to the conclusion that for most parts of the area the ground-water supply is ample to furnish the present needs. Evidence indicates "that further development of irrigation with water pumped from wells can be made in the Platte Valley and in some of the valleys of the smaller streams. Additional irrigation wells can be drilled on the plains to the south, but because the ground-water supply in that area is limited chiefly to percolation from the Platte Valley, the development of large irrigation projects depending on wells is not feasible.

The Nebraska Geological Survey, the University of Nebraska State Museum, and the Department of Geology at the University of Nebraska have approved the foregoing restriction of the term Grand Island and the adoption of the new name Red Cloud sand and gravel, and these names will be used in future Nebraska publications as herein defined. It may be necessary to apply the hyphenated term Red Cloud-Grand Island to some subsurface intervals in the Pleistocene basin areas where the two formations cannot be separated satisfactorily. However, the subsurface studies of the Nebraska Geological Survey indicate that the Red Cloud-Grand Island interval in many test holes can be separated into a lower sand and gravel grading from coarse-textured at the base to fine-textured above, overlain by a higher sand and gravel with similar textural characteristics.

Russia possesses unmeasured elements of strength and vitality. The realm of the Russian Bear encompasses a relatively sparsely settled do- main of vast extent, and contains known but unestimated natural re- sources of every kind: fuel in the forms of coal and oil; iron, copper, manganese, and other common minerals; unknown but large deposits of probably every kind of strategic mineral; and agricultural potentiali- ties unequalled anywhere, perhaps not even in North America. Perhaps the Ukraine alone contains more natural wealth than all the rest of Europe. And Russia contains two hundred millions or more of the world's population, counting the more recent acquisitions. Furthermore, great internal expansion and materialistic development are taking place and will, without undue crowding, continue for a long time within this vast region.

This is one of the smaller counties of the state and is rectangular in shape. It contains twelve congressional townships, with approximately 432 square miles or 276,480 acres.1 The twelve congressional townships are everywhere conterminous with the civil townships, each containing thirty-six sections, and comprise townships 71, 72 and 73 north and ranges 20, 21, 22 and 23 west of the Fifth Principal Meridian. The latitude and longitude of the Court House in Chariton, the county seat, are 41° 00' 55" N. and 93° 18' 22" W.

This county is underlain by formations of the Des Moines series of the Pennsylvanian system' arid' has become an important coal producing county in the last few years. It is served by main lines of the Chicago, Rock Island and Pacific and the Chicago, Burlington and Quincy railroads.

Every Paleozoic system below the Pennsylvanian is represented by identifiable rocks in the subsurface section of Nebraska, and all are present at least east of the buried Nemaha ridge. The exact subsurface distribution of each of the Paleozoic systems is not yet known with certainty. Apparently all formations are the same and are continuous with the pre-Pennsylvanian rocks of Iowa. The Cambrian and Ordovician rocks of the southern part of the state are also quite similar to correlative formations in Oklahoma. The fact that most of the deep test wells so far drilled in the state have been located on structural or on monadnock-like pre-Cambrian "highs" has precluded the discovery of many pre-Pennsylvanian Paleozoic rocks, which do occur in the "basins." This has led to the misconception that Nebraska was not invaded by all of the Paleozoic inundations.

The Carboniferous outcrops are confined to some eight or ten counties in the extreme southeastern corner of the state, and though covered heavily by glacial clays, bold exposures occur in proximity to the bolder streams, especially the Missouri River. About a mile south of Peru, on the Missouri River front, the bluffs are limestones interbedded with thin layers of shale. But within a few hundred feet the shale thickens until the limestone pinches out altogether, and within as many feet the shale becomes increasingly arenaceous until it merges into a bed of massive cross-bedded sandstone. Within a mile this order is symmetrically reversed.