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The Carboniferous system extends over the largest part of the country examined during this trip, and to it the most of the time was devoted.

No attempt is here made to separate the Subcarboniferous from the Carboniferous. In fact I am not certain that the Subcarboniferous formation occurs. The strata of the entire series, so far as I observed them, are conformable and the fossils found in the lower part of the formation were not characteristic of the Subcarboniferous, but are those which are for the most part embraced in the fauna of the coal measures. I am certain, however, that there is a section at least 400 feet thick, lower than the strata of the coal measures which are found in the northern part of the State.

The Permian formation was clearly distinguished overlying the coal measures on the west.

The general dip of the strata of this system is to the northwest at about 30 feet to the mile, except near Lampasas, where the dip is to the northeast, which may be accounted for either by the existence of an anticlinal in the western part of Lampasas County, or possibly by faulting.

The strata of the Carboniferous are composed of limestones, sandstones, clay beds, and shales, with three or more beds of coal. On top of the measures in many places is a bed of conglomerate similar to that found overlying the coal measures in the northern part of the State.

The measures are about 1600 feet thick, so far as examined, although their upper part was not reached. In many places the strata are so deeply covered up with drift that it was impossible to get a continuous section, and the thickness is therefore estimated by the known dip of the strata, where a section could not be made by actual measurement. Many sections were made at different localities, with the hope of being able to secure a continuous section, but there are gaps that can only be filled by estimates of thickness, based on dip and the distance occupied by the wanting section. Enough, however, has been done to give a very correct idea of this formation, which can be worked out more in detail in the future.

The Carboniferous limestone was first observed at the mineral springs of Lampasas, where the water issues from a fissure in a blue limestone belonging to this formation. The limestone dips east at an angle of one and one-half degrees. On the top of the limestone is a yellowish marl which seems to be more disturbed or flexed than the underlying material. The limestone contains such distinctive fossils as Spirifer cameratus, Productus costatus, P. "

The dips here given are from careful instrumental measurements-frequently of lines of considerable length-by Mr. C. C. McCulloch, Jr.