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six inches at their greatest thickness. This bluish green marl is known to be over twenty feet thick, and rests upon a brown laminated sand.

Southwest of the prairie,along Hurricane bayou and in Collin's branch, where the blue and brown marls and sands and carbonate of iron appear in the banks associated with each other, the fossils are numerous and mostly of a different variety. The fauna here is chiefly made up of Volutalithes, Surcula, Pleurotoma, Fusus, Pyrula, Natica, Dentalium, Plicatula filamentosa, Conus and others—the Plicatula being especially plentiful.

LOWER EOCENE.

The deposits here classed as Lower Eocene have already been described by Dr. Penrose, in the First Annual Report, page 19, under the title of the Basal Clays. Additional examinations during the last summer place these deposits as resting upon the Cretaceous marls two miles west of Muddy Cedar creek, and their upper or last deposits passing under an iron-bearing yellowish gray sand about four miles east of Wills Point, thus giving these deposits a width of sixteen miles. Their thickness is here placed at 250 feet.

In Dr. Penrose's report, already mentioned, the fossiliferous limestones are considered the lowermost beds, but this season's examination has resulted in adding a series of dark blue laminated fossiliferous clays and brown sands to the base of these beds and between the limestones and the Cretaceous marls.

The fauna of these deposits is very scanty, and consists mostly of a few small bivalve shells, most of which are very delicate and difficult to retain long enough for identification.

The limestone bowlders, hitherto considered as non-fossiliferous, show upon examination to contain a few fragments of undetermined gasteropods.

ECONOMIC GEOLOGY.

In addition to the lines of sections and other stratigraphical work during the season, investigations and examinations were made in Van Zandt, Wood and Houston counties into the economic conditions and production of the following articles, viz: Salt, lignite, iron ores, green- sand marls, building stones and clays. The last named were gathered from various regions during the season's work.

SALT.

There are various salines scattered throughout East Texas, all or nearly all of which have, at different periods, been utilized for the production of salt, but the one to which most attention was paid, chiefly on account of its lying within the line of sections made and because of its being the only one now being utilized, was Grand Saline, in Van Zandt county. This is the only saline in East Texas producing salt for commercial purposes.