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Rochelle northeastward to the Colorado, along Deep Creek, and just east of the town of Milburn.

At its southwestern end it is coarsely conglomeritic, and contains pebbles often weighing a pound or two. These pebbles are almost entirely well rounded flint of various colors, derived directly from the Silurian, and cemented in some places by iron and in others by silica. Near Rochelle, the conglomerate attains a maximum thickness of fifty feet, and because of its development at Rochelle I propose the name of Rochelle Conglomerate bed of the Richland Sandstone division. Traced northeastward the conglomerate becomes finer grained, is very much cross-bedded, is interbedded with layers of sandstone, and eventually becomes, near the Colorado, a conglomeritic sandstone with thin layers of conglomerate. East of Deep Creek a portion of the Rochelle Conglomerate is buried beneath the Cretaceous, an eastern extension of the Brady Mountain Cretaceous beds, and it is in this buried portion that the change from conglomerate to conglomeritic sandstone takes place. Where it is again uncovered east of Milburn it is difficult to separate the Rochelle Conglomerate from the upper layer of the Richland Sandstone. Northeast of here the conglomerate bed becomes less distinct, but it may be traced as a distinctly conglomeritic sandstone band across Pecan Bayou to the Cretaceous.

The entire area of the Carboniferous included in the Richland Sandstone division, from its upper bed, the Rochelle Conglomerate, to the Lower Carboniferous, is barren of coal measures. Thin seams of coal may possibly be found, but no beds of a paying nature are to be expected in this formation. A condition of rapid deposition with abundance of coarse sediment, accompanied by a gradual subsidence, seems to have prevailed. That coal plants were growing on the neighboring lands is proved by their presence as casts in the sandstone, and undoubtedly thin seams of coal and carbonaceous shale will be found; but the conditions which favored the accumulation of coal beds had not yet arrived.

With the close of the sandstone era, as marked by the deposition of the Rochelle Conglomerate, a condition of quiet water and finer sediment prevailed. With the new conditions a new series of beds began to be formed, and for these I propose the name "Milburn Shales." The southwestern extension of these shales is hidden beneath the Cretaceous of Brady Mountains, but in the neighborhood of Milburn they are well shown. They are capped by limestone and underlain by the Rochelle Conglomerate. Near the head of Deep Creek the lower layer is shaly sandstone with a thickness of 60 feet. This shale grades from the conglomerate below to an argillaceous shale above, and is overlaid by a deposit of clay 15 feet thick, with scattered nodules of clay ironstone. Some gypsum is also present in this layer. Above