thru newspapers, thru reports of the Weather Bureau, thru the LightHouse Board, and by special correspondence. The severe earthquake which occurred in California on the morning of April 18 was made the subject of a special investigation, in which the Geological Survey cooperated with the State of California and the Carnegie Institution. Two officers of the Geological Survey became members of the commission appointed by Governor Pardee, of California, and a third was temporarily detailed to assist in the work. This commission is studying the phenomena of the earthquake in a systematic manner, and has already made a preliminary report. The Geological Survey has also investigated the injury to buildings and other structures in San Francisco and vicinity, for the purpose of ascertaining what materials and forms of construction are best adapted to withstand earthquake vibrations.

PALEONTOLOGIC WORK.

In addition to the usual routine work of the paleontologists-that of aiding, by the identification of contained fossils, in the determination of questions of age and stratigraphy-which is performed for members of the Survey and the various State surveys, many special paleontologic investigations were carried on during the year.

Tertiary and Quaternary.-The study of the marine Tertiary fauna of the Pacific coast, which has been of fundamental importance in determining the oil and petroleum horizons of that region, was considerably advanced during the year, especially by the large collections of fossils obtained in Fresno, King, Kern, and San Luis Obispo counties, Cal. Satisfactory progress was made in the preparation of a monograph on this fauna, and in connection with it a bibliography and reference card catalog of the several thousand Tertiary and Quaternary species of the coast was prepared in order to facilitate the identification and study of fossils from those horizons.

The knowledge of Tertiary faunas was especially augmented by a large collection of Pliocene and Pleistocene fossils from Port Limon, Costa Rica, which have an important bearing upon the relations of the Tertiary of California to that of the Gulf of Mexico.

The monograph on the Tertiary corals of North America was also well advanced, and considerable progress was made in the preparation of a report on the Miocene of the Coos Bay region of Oregon.

The study of large collections of fossils from Georgia, gathered in connection with the investigation of underground waters, resulted in mapping the Tertiary formations of a large part of southeastern Georgia of which previously little or nothing was known, while an interesting collection from the Oligocene of Florida threw much light on the Tertiary of that region.

Cretaceous. Considerable progress was made in the study and description of the Lower Cretaceous fauna of Texas, a work which

has been in preparation for several years, such time as could be spared from immediately pressing duties being devoted to it.

Triassic. Satisfactory progress was made in the preparation of the monograph on the Triassic cephalopods of America. A large quantity of valuable material was collected from the Upper Trias of Shasta County, Cal., and that previously collected from the Triassic of Nevada, Idaho, and California was classified and studied in detail. The work in Shasta County resulted in clarifying certain stratigraphic problems of that region which have a direct bearing upon the study of the economic resources.

Carboniferous.-The manuscript for a professional paper on the unique Guadalupian fauna of Texas, which is widely different from the typical Pennsylvanian, from the Permian of the Mississippi Valley, and from the Russian Permian, altho bearing some resemblances to the latter, was completed and submitted for publication, and the manuscript for a professional paper on the Lower Carboniferous orebearing beds of Missouri was partly written. The latter study was made in order to facilitate the correlation of the different ore-bearing horizons of the Missisippian series with one another and with the standard section of the Mississippi Valley in Missouri and Iowa.

The Devono-Carboniferous series of Pennsylvania was made the subject of a special geologic and paleontologic study, but additional field work will be necessary before the results can be prepared for publication.

Devonian and Silurian.-The Devonian and Silurian stratigraphy and faunas were the subject of an investigation with reference to the modifications which they exhibit in passing north and northwest from central Kentucky to Wisconsin, a question which has an important bearing on the distribution of the lead and zinc deposits of that region.

Cambrian.-A monograph on the Cambrian brachiopods was brought very nearly to completion and will be submitted for publication early in the next year. Field investigations in the extensively developed Cambrian formations of western Montana and central Utah were continued.

General.-Special paleontologic field studies were made in southeastern Alaska for the purpose of determining the limits of the principal geologic horizons and the order of succession. A bulletin on the paleontology of the Santa Cruz region in California, based on material gathered in connection with the areal and economic survey of that quadrangle, was well advanced. The monograph on the Ceratopsia was completed and is now in the hands of the printer, and considerable progress was made on the Sauropoda and Titanothere monographs, but owing to the magnitude and difficulty of the tasks additional work remains to be done. This study is being greatly facilitated by the notes and collections incidentally made by geologists

engaged in other investigations. Special collections of fossils were made in the vicinity of Murfreesboro, N. C., for the purpose of recovering species obtained in that locality by Wagner about 1832 and hitherto not represented in the Survey collections.

A monograph on the fossil flora of the Laramie, the great coalbearing formation of the West, was well advanced, and will probably be finished next year. This monograph is one of the results of a special investigation made for the purpose of affording an easy means of identifying this formation and aiding in the classification of the coals of the different localities.

In connection with the mapping of the areal geology of the Kenova quadrangle, in Kentucky, Ohio, and West Virginia, a special study was made of the paleobotany of the Upper Carboniferous formations of that region for the purpose of ascertaining the extent of the basal unconformity and to aid in correlating the succeeding Coal Measures groups with the rocks in Pennsylvania. A similar study was made in the Birmingham, Ala., quadrangle, which it is hoped will establish the correlation of the enormously thickened coal-bearing section of that State with the formation recognized in the basins farther north in the Appalachian trough and permit the identification of the equivalents of the minor subdivisions or coal groups in the several detached basins.

At the request of the chief of the Brazilian coal commission several collections of fossil plants from the coal fields of Santa Catharina and Rio Grande do Sul were examined and reported upon by Survey paleobotanists, and on the completion of the work the material, which is of considerable scientific value, was presented to the United States National Museum by the Brazilian commission.

Satisfactory progress was made in the work on the bibliography and compendium of paleobotany, which not only serves as a working guide for Survey paleobotanists but is consulted by American paleobotanists generally, and frequently by those of other countries.

PETROGRAPHIC LABORATORY.

The petrographic laboratory, in which three persons were employed continuously and one temporarily, remained in charge of the chief of the section of petrology. Its high record of efficiency was maintained thruout the year, the total output being as follows: Thin sections of average size, 6,295; large or difficult sections, 257; saw cuts, 1,134; surfaces polished, 85. The petrographic reference collection also remained in charge of the chief of the section of petrology, and was substantially increased during the year.

DIVISION OF ALASKAN MINERAL RESOURCES.

The work of the division of Alaskan mineral resources was carried on under the appropriation of $80,000 made for "a continuation of the investigations of the mineral resources of 'Alaska." Under this authority the following classes of work were done: Reconnaissance and detailed geologic surveys; special investigations of mineral deposits; reconnaissance and detailed topographic surveys.

SEASON OF 1905.

The permanent technical field personnel of the division embraced 11 geologists on annual salaries, 1 geologist on a per diem salary, and 4 topographers. One paleontologist gave a part of his time to the Alaskan work. The office work included 1 geologist, 1 clerk, and 1 typewriter on annual salaries, and 1 typewriter holding a temporary appointment. In addition to the regular technical force, 4 geologic and 4 topographic assistants and 1 special assistant, together with 28 packers, cooks, etc., were employed in Alaska during the summer of 1905.

Nine parties were engaged in field work during the open season, from about May 15 to October 15, in 1905. Several of these were subdivided after reaching Alaska, making 14 parties in all.

Southeastern Alaska.-A party of 2 geologists, a part of the time assisted by a paleontologist, continued the reconnaissance work in the Panhandle. The preliminary study of the geology and mineral resources of the Ketchikan and Wrangell districts was completed. An outline of the results has been published in Bulletin No. 284 and a more complete statement is in preparation.

Yakutat Bay. Three geologists were engaged in this field from June until September. A geologic reconnaissance was completed and a preliminary statement of results has been published in Bulletin No. 284. In connection with the survey of the gold-bearing beach gravels and the lignite deposits, a special study was made of the glaciers of this region, of the evidence of former glaciation, and of the remarkable deformation of the earth's crust which occurred during the earthquake shock of September, 1899. A detailed report on these investigations is in preparation.

Controller Bay. Two geologists and 2 topographers were employed in detailed surveys in this field from May until October. Topographic surveys of 430 square miles, lying between 60 and 60° 30′ north latitude and 139° 45′ and 144° 35' west longitude, were completed for publication on a scale of 1:62,500, with 50-foot contours. Of levels, 97 miles were run and 9 permanent bench marks were set. Of traverse, 183 miles were run. Reconnaissance topographic surveys (1:250,000)

were also carried over about 200 square miles of additional area. The geologists made surveys of about the same area as the topographers, and made a special study of the coal fields of the region. An outline of the important results is contained in Bulletin No. 284.

Prince William Sound.-Two geologists were engaged from June 25 to September 15 in making a reconnaissance of the shores of Prince William Sound. All the known copper deposits were examined in detail. A preliminary statement of results has been published (Bulletin No. 284) and the final report is in preparation.

Matanuska Valley.-The coal fields of this district were hastily examined by a geologist during the month of August, and a statement of the results is in press (Bulletin No. 289).

Herendeen Bay.-A rapid reconnaissance of the coal-bearing rocks of this region was made by a geologist in June, 1905, and the results have been published in Bulletin No. 284.

Seward Peninsula.-Three topographers, working from June to October, 1905, completed the survey of the areas of the Solomon Special and the Casadepaga Special maps, embraced between longitude 164° and 164° 30' and latitude 64° 30' and 65°, and including 470 square miles. The scale was 1:62,500, with 25-foot contours. Levels to the extent of 93.9 miles were run and 17 permanent bench marks were established.

Detailed studies of an area of about 300 square miles in the Nome region were made by two geologists during the summer of 1905. In addition to this the same men made a further study of the tin deposits at York and of the gold placers of the Solomon River and Ophir Creek regions. The results of the latter work are contained in Bulletin No. 284.

Yukon-Tanana region.-Topographic reconnaissance surveys (1: 250,000, contours 200 feet) were extended over an area of 4,300 square miles by two topographic parties. The mapped area includes a part of the Birch Creek, Beaver Creek, and Tolovana River basins. The work was controlled by triangulation carried westward from points previously established in the Birch Creek basin. A part of the area covered by these surveys is included in the Circle quadrangle, in the Yukon-Tanana region, a report on which is in press (Bulletin No. 295). A geologist accompanied the topographic party, working in the Beaver Creek region, and made an areal reconnaissance of the area traversed, and the results have been published in Bulletin No. 284. The field season was cut short by the early snow which fell on September 4. A party of two geologists carried a reconnaissance westward from the international boundary at the head of Sixtymile Creek to the mouth of Delta River and thence to Fairbanks. A part of the results of this work is in print (Bulletin No. 284).