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class of ores are the concretions which occur in certain layers among the Arietina limestones, and at another higher horizon of the Cretaceous outcropping south of Cline postoffice near the summit of the hills. The ore is globular, varying in size from that of a pea to balls one or two inches in diameter, the bullet size being most common. Perhaps, if these could be gathered in sufficient quantity, they might become of some value as iron producers, but there are probably no localities where the cost of collection would not preclude their industrial employment.

With the immense deposits of choice hard ores and the limonitic products of the Central Mineral Region so near at hand, it does not seem reasonable to look for the upbuilding of any very extensive iron smelting business in this region. As a means of local supply for a limited product, there may eventually be demand enough to stimulate mining in a degree, but there is much more prospect that the Del Rio and Montell mines will be called upon to supply a market for raw material to be used as paint, for which much of the ore is well adapted.

KAOLIN.

The region of the vein of iron ores is practically the area within which the deposits of kaolin occur, and as in the former case, the relations to the basalt dykes is unmistakable also in the latter accummulations. There is, however, a peculiar tendency of the kaolin banks to conform to the drainage courses, i. e. to lie in local basins. More study will be required to determine whether this apparent feature is strictly real; although the best deposits of kaolin are known to be in situations near the basalt where there has been the best opportunity for the silting action of incipient streams. There is considerable variation of quality, the best known workings being those which lie off the main road from Barksdale to Leaky, in Edwards county, about four miles from the latter town. Here the product has been mined from pits dug fifteen to twenty feet through the overlying gravels. Tests to be made in the chemical laboratory of the Survey must be awaited before a full report can be made of the value of the deposits. It is very probable that careful search over the area of basaltic outbursts will be rewarded' by other discoveries of this material. I have taken samples from the Nueces valley not far below the point where the basalt dykes cross that stream, and from similar situations elsewhere.

It would seem that both the kaolin and the ochres are direct products of decomposition of the igneous intrusions, the former being usually or commonly reasserted by aqueous action and transported to greater or less distances from the point of origin, the latter being mostly formed in the position in which it now lies, or occasionally in beds not so far removed from the original locas as the kaolin, which would be more easily transported, of course.

The kaolin is very well placed for economical working, and if it be of