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in them. Those so far observed in Texas formations will be found enumerated in the general description.

A reference to the table on Plate III will give at a glance the general relation existing between each formation and those adjacent. From this table it will be seen that we have in Texas representatives of nearly every group and system known in the United States, and also the Lower Cretaceous and Lower Permian series, which are rarely represented elsewhere on this continent. The detail and full definition of the boundaries, character, and resources of each of these formations remains as the future work of the Survey.

The work of the past year has mainly been directed to the acquirement of a knowledge of the different formations occurring in the State, the character of materials composing them, their economic possibilities, and some idea of their extent, as a basis for our future work. The work was necessarily of the character of a reconnoissance, and there still remains much of the same kind of work to be done, but the main facts as here presented give us a good working knowledge of these conditions, and enable us to formulate our plans in such manner as will secure more rapid and satisfactory returns in the future.

In a general geologic description of a region it is customary to begin with its older rocks, as being not only the first in time of formation but in a measure the source from which were derived the greater part of the materials entering into the composition of those that succeed them. In reversing this method, as is done in the following pages, respect has been had merely to convenience of description by beginning at those formations the main features of which are best known to our general public, and therefore most readily explainable in a simple manner.

The exposed portions of those formations which occupy the Coast District (which is, as has been stated, the continuation of that bordering the Gulf shore of the States east of us) comprise the Coastal Clays, the entire Gulf Tertiary Section, and part of the Cretaceous System, and these are arranged in belts, the general boundaries of which are approximately parallel to the present coast line. The normal dip or inclination of the strata of these formations is towards the southeast, and, while it is very gentle, it is greater than the average slope of the present surface in the same direction, and therefore the newest beds are