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have no definite detailed account, except in the Central Region, and in the later ones little attention was given to the subject. The State and its problems were too great to be compressed into the small amount of work which could be done under the appropriations.

All other work has been on detached areas, and for most part the results are summed up in short magazine articles. Later, good work has been done by Mr. R. T. Hill, who has done much to give us a clear understanding of the Cretaceous, but even this is still very incomplete, and we may well say that the principal facts of our geologic history as a whole are even to-day unknown, except in so far as the work of the present survey has brought them to light.

The plan adopted consists in giving the geologist in charge of the field party a definite line of work under general instructions, leaving the greater part of the details to be determined by himself, he being directly responsible to the State Geologist for the results. This works most admirably in practice, for while it furnishes the results as desired and planned for by the State Geologist, it allows the individuality of each geologist to be clearly seen through his report. Many of the minor details were settled by conference during the visits of the State Geologist to the different camps.

The present condition of the field parties, the amount of work they have accomplished, and the spirit in which it has been done, is proof of the satisfactoriness of the arrangements.

A knowledge of the general geology being a prime necessity in the carrying out of the objects of the Survey, the work of the present year was distributed in such a manner that while each field party had some distinct economic feature as a basis for the season's work, its relations and position were such as to necessitate a study of the details of the formation in which it occurred.

Mr. Penrose, in his report on the iron ores of Eastern Texas, necessarily gives the general geology of the Tertiary and later formations in which they occur, in order to show the manner of their deposition, their origin, character, and their relations to each other and to the formations containing them. The next older formation, the"

A detailed account of all work done previous to the organization of the present survey will be found in Bulletin No. 45 of the United States Geological Survey. "Present Condition of Knowledge of the Geology of Texas." R. T. Hill.