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Portions of the section are stratified into bands of one foot or more, but a large majority of the strata are massive, while the whole series, except a few alternating marls and layers of the Trinity, are remarkably free from lamination.

The writer believes the day will come when it will not be considered essential to discuss together the Comanche series and the Upper Cretaceous series, so different are they in every geologic aspect.

There can be but little doubt that the rocks now composing the Comanche series were elevated into dry land, that the succeeding land epoch continued as long as the time of deposition of either of the including series, and that the rocks of the Upper series were largely derived from the underlying Comanche strata, and laid down during an entirely different and later oceanic subsidence.

The Upper series has been well studied in the Northwestern States, by the late Prof. F. B. Meek, the geologist who has contributed the most that is known concerning the Cretaceous formations of that country. His descriptions are found in a volume entitled "A Report of the Invertebrate Cretaceous and Tertiary Fossils of the Upper Missouri Country." By F. B. Meek, Washington, 1876. The Upper Cretaceous series of Texas, while varying in many specific details from the section therein described, is so generically allied that it is evident those variations are merely local differences in the same great subsidence, and that nothing but long and arduous labor, to be yet performed, will reveal their exact affinities.

The Upper Cretaceous series of Texas is divided into five conspicuous lithologic divisions, each unmistakable in its stratigraphic and topographic individuality, yet gradating into its adjacent divisions. Not one of these divisions has been minutely or systematically studied, further than here presented, although work in this direction is now in progress.

North of the Brazos to Red River the base of the Upper series is composed of a brown, more or less ferruginous, predominately sandy littoral deposit, resting unconformably upon various horizons of the semi-chalky beds of the Washita division. These sandy deposits present an infinite variety of conditions of cross-bedding, clay intercalations, lignitic patches, and variation in fineness of size and angularity of the uncemented particles, characteristic of typical littoral deposits, while occasionally there are found fossiliferous horizons. One of these on Timber Creek, near Lewisville in Denton County, occurred in association with lignite and cross-bedded sands, and was composed