From outline: This essay comprises, first, a general discussion of the limitations of the term Eocene as employed in American geology. The two-fold character of the Tertiary (1. Eocene, 2. Neocene) in America is insisted on. After a somewhat extended review of the literature, in which the various opinions upon disputed points are especially considered, a general study of the stratigraphical, paleontological, and topographical characteristics of the Eocene in the various portions of the country is undertaken.

From introduction: In his report on the Geology of Pennsylvania,' Professor Lesley summarizes his opinion upon the geology of the South Mountains and Formation No. 1. In this, Formation No. 1 is referred to the Upper Cambrian, and a detailed description is given of its occurrence along the South Mountains and across the State to the Delaware. The superjacent limestone, No. 2, is referred to the Ordovician.' Fuller reference will be made to Professor Lesley's descriptions in speaking of the rocks of York County.

From outline: This hook is a review of the present state of knowledge of the general structure of the pre-Cambrian rocks of the United States and Canada. The material contained in the historical chapters is of two kinds: Summaries of all articles pertaining to the subject considered, and summaries of the conclusions which appear to be established. The first represents the substance of the literature; the second brings together the important ascertained structural facts, and often times becomes a more or less extended discussion. The final chapter covers the same grounds as the historical chapters for the various pre-Cambrian in general successions proposed by different authors, and also contains a discussion of results and the principles upon which they are based. Within the chapters, individual districts or regions are given separate sections, and the summary of literature for each is arranged in chronological order.

From letter of transmittal: SIR: I beg to transmit herewith, for publication as a bulletin, a gazetteer of Kansas.

From letter of transmittal: SIR: I have the honor to. transmit herewith a geographic dictionary of New Jersey.

From introduction: The triangulation of the U. S. Geological Survey is executed solely for the primary control of topographic work upon scales not exceeding 1: 62500. The extreme of accuracy has therefore not been sought, but only such a degree of accuracy as to insure that the maximum accumulated error be imperceptible upon the maps.

From introduction: In December, 1892, as the result of field work on the part of Dr. G. H. Williams in the northern and of the writer in the southern portion of South Mountain, there appeared a preliminary description of two of the rock types, in which their identification as ancient volcanics was announced. In this bulletin it is proposed to substantiate that identification with more detailed proof. It is further proposed to show that these ancient igneous rocks were, at the time of their consolidation, identical in character with their recent volcanic analogues, and that their present differences are due to subsequent changes, chief among which has been devitrification. It is also proposed to recognize these facts in the nomenclature.

From introduction: The Three Forks sheet of Montana includes the area lying between the parallels of 450 and 460, and extending from longitude 111 to 1120. The three forks of the Missouri river unite in the north central portion of this area about 5 miles south of the northern line of the map.

From introduction: In presenting this paper the writer has two objects in view. The first is to add to the general knowledge respecting the geology of this central district [Appalachian coal basin]. The groups determined in this region will be carried over the adjoining territory if they can be distinguished and they afford a type-section of the Coal-measures where they are probably best developed. The results are not put forth as final, but as representing the most probable conclusions from the observed facts.

From preface: The following review of one of the Upper Cretaceous faunas as developed in the interior region of the United States has grown out of the study of a collection of fossils found by me in Huerfano park and adjacent localities in southern Colorado. This collection, the greater part of which was obtained during the summer of 1890, proved to be especially interesting because it afforded data for the closer correlation of certain Cretaceous strata in Utah with those east of the mountains, besides adding a considerable number of new species to the fauna of the Colorado formation. Dr. C. A. White, under whose direction the field work was done, generously assigned these fossils to me for study with a view to publishing the results, and I am greatly indebted to his sympathetic aid in every phase of the work.

From introduction: An examination of the country described in this paper was ordered by the Director of the U. S. Geological Survey at the request of persons interested in the development of the state of Washington, for the purpose of ascertaining how far the geological structure of the arid portion of the state favored the hope of obtaining artesian water for irrigation.

From outline: This paper, after discussing general principles connected with the study and description of the Tertiary or Cenozoic rocks and fossils contained in them, takes up the Neocene deposits of the United States in particular. A chapter is devoted to a summary of what is known in regard to the Neocene of the eastern coast of the United States, each State in geographical order being separately considered, beginning at the north.

From outline: The primary object of this bulletin is the presentation of a summary of our present knowledge of the North American Cretaceons and a discussion of the system as it is developed on this continent, discussion of or direct reference to the details of the system as it is developed in other parts of the world being omitted.

From preface: This memoir is a general study of the region described, and not a detailed report. The field work upon which it is based formed a part of the work of mapping the areal geology of the Little Belt Mountains sheet of the Geological Survey. The topographic map, made in 1882 by the Northern Transcontinental Survey, is too small in scale and too general in character to warrant more detailed work; but as the facts obtained are of interest, and the region is one of economic importance, it has been considered worthy of a special treatment.

From introduction: For several years the Division of Topography of the United States Geological Survey has been engaged in compiling positions determined within the United States which are believed to be of sufficient accuracy for use in the preparation of its maps. This compilation has been found extremely useful in the office, and it is believed that its usefulness will be greatly extended by placing it before the public. This list comprises between 9,000 and 10,000 positions. To publish it in extenso, with descriptions of the stations, their latitudes and longitudes, the distances and azimuths to neighboring stations, and the methods of determination, would extend this bulletin beyond all reasonable limits. To avoid making too bulky a volume, it has been decided to publish merely the latitudes and longitudes, with abbreviations indicating the authority, and references to the publications in which other data relating to the positions may be found.

From introduction: The field relationships of the rocks described in the following paper were studied during the summers of 1895 and 1896, while I was engaged in geologically mapping portions of the Sonora and Big Trees quadrangles, under the direction of Mr. H. W. Turner.

Preface: In the following bulletin I have brought together the more important results of experiments in high temperatures, made since the publication of my bulletin on the thermoelectric measurement of high temperatures.' Chapter I, in addition to pointing out certain inherent relations between metallic vapor tensions, has a direct bearing on pyrometry. Chapters 11 and ii are of geological importance, and the work was done for Mr. Clarence King. Chapter ii shows that in case of the igneous fusion of basic magma, the passage from liquid to solid is one of contraction, and measures the difference of specific volumes at the solidifying temperature. Chapter iii contains a full account of the thermal capacity of the same rock under the same conditions, and by aid of Chapter it leads to a numerical value for the relation of melting point to pressure, for silicates.

From outline: The present paper gives a detailed account of the glaciation of the Snowy mountains and of the upper valleys of the Yellowstone, whose deposits show an unusual phase of alpine glaciation. The evidence thus far gathered shows that a large body of ice, originating in the ice sheets of the Yellowstone National Park, pushed northward, filling the upper valleys of the Yellowstone and extending down that stream 36 miles north of the park boundary.

From introduction: The object of this memoir is to give some account of the geology of the lower Potomac formation in Virginia, where it is perhaps most typically developed.

Introduction: By way of introduction a section will be described across the Devonian of the northeastern part of Monroe County, Pa., along the line of Brodhead Creek and the Delaware, Lackawanna and Western Railroad. The base of this section will rest on the Corniferous limestone well exposed in a railroad cut a mile south of East Stroudsburg and the termination will b6 in the Pocono, as exposed on the Pocono Mountains, from Mount Pocono to the ridge northwest of Tobyhanna.

From letter of transmittal: The results contained in this report are the product of investigations conducted during the past three months. These investigations were in extension of the work on which was based my report, as State geologist of Missouri, on the lead and zinc deposits of the whole State.

From preface: The preparation of this paper is due to the fact that the eruptive rocks occurring on Pigeon point, Minnesota, may be taken as types of similar eruptives found so widely spread over the Huronian and Keweenawan areas surrounding Lake Superior, and to the peculiar nature of the alteration these have superinduced in the fragmental rocks through which they have broken.

Revision of the genera and subgenera of voles and lemmings with comparison between North American and European.

Classification of more than 3,000 bats to enable correct specimen identification based upon material contained in the collection of the Biological Survey of the U.S. Department of Agriculture.