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Several weeks were devoted to the procurement of suitable illustrations of the Cretaceous areas, and for this purpose I have secured through the agency of Mr. C. W. Eddy, the photographer of the Survey, a magnificent suite of negatives, illustrating the characteristic structure, weathering, topography, building material, fossils, and vegetation of the Cretaceous regions. These pictures will be invaluable in illustrating the unique natural conditions of the region.

I have spent much time upon the necessary work of preparing the results of observations for publication, and in study of material. In order to render the work accurate much library research has been necessary, and this was done in the libraries of the East, during the summer, in ascertaining the work of previous investigators, in order to avoid unnecessary duplication, and in the verification of details. Many pages of manuscript have been prepared, and numerous technical papers published, containing concise preliminary definitions, which must necessarily precede all results of permanent economic value.

Messrs. Taff, McCulloch, and Stone have all been employed for a few weeks each in office work for my division.

Most of the details of the work have been carried out by the able young assistants whom you have placed at my disposal.

Mr. J. A. Taff.—One of these, Mr. J. A. Taff, has been constantly engaged upon the work, he having general charge of the field work. The faithfulness and accuracy of his labors are worthy of special commendation. In addition to his services in the field, he has done valuable work as a draughtsman in the office. He has traced, mostly on foot, over 2000 miles of partings, and accurately located them. In addition, he has made over 200 miles of instrumental cross-sections. A brief summary of his work is as follows:

The Basal Trinity Beds were traced from the Colorado River, at the west line of Travis County, through Burnet, Lampasas, Mills, Brown, Comanche, Erath, Eastland, Hood, Parker, Jack, Wise, Montague, and Cooke counties to Red River, a distance of 400 miles.

A section was made along Red River basin from Nacona, Montague County, through Montague and Cooke to Denison, in Grayson County; length 10 miles. A section was next made across Red River basin, at Gainesville, Cooke County, followed by one across Red River basin at Denison. The