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WORK OF THE PAST SEASON.

We began the work of the present season at a point on the San Saba river sixteen miles east of Menardville. This is the extreme southern outcrop of the Carboniferous formation in Central Texas, which is here composed of massive limestone in beds dipping to the southeast, containing the well known Carboniferous fossils Productus punctatus, Productus costatus and Terebratula subtillita. South of this locality the heavy beds of the Cretaceous overlie the Carboniferous.

Our route was westward along the valley of the San Saba river. About one mile from the place of beginning, the Carboniferous strata, which had been dipping to the eastward, changed their dip to the north-west, and at four miles, at the mouth of Crawford's creek, passed under the red clay beds of the Cretaceous. The following section was made here:

• No. 5 of this section is composed of rounded pebbles and larger bowlders, the latter of limestone and flints from the Cretaceous. The top of this bed is loose material, but has the same composition as the more firmly imbedded material in the calcareous matrix at its base.
• No. 4. is a bright yellowish clay with some quartz sand.
• No. 3 is a greenish sand of white rather large quartz sand.
• No. 2 is a bright vermilion red clay, occasionally interstratified with a coarse siliceous grit.
• No. 1 is a coarse massive grit of white and red quartz. This is not in regular layers, but only in isolated masses.

Plenty of timber along the river of pecan, overcup, elm and hackberry; mesquite in the valleys. Soils are black and reddish loams.

We continued up the valley of the river, crossing it twice, to the town of Menardville. The following section was made at a hill eight miles east of the town: