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this report, as they must with all who have to do with the Paleozoic formations of the states adjacent to Tennessee, for the descriptions and classifications of Dr. Safford are remarkably true to nature. Chapters III to VI inclusive are devoted to a general description of the lithological and other characters of the different formations which make up the area under consideration in Georgia. The Ocoee group, which Dr. Safford places at the base of the Cambrian in Tennessee, or beneath the oldest of the fossiliferous strata, is mentioned by Dr. Spencer, but he does not enter into its detailed description. This group of semi-crystalline slates, often designated as hydro-mica schists, talcoid schists, and formerly as talcose schists, and which bears the greater part of the auriferous quartz veins in Georgia and Alabama, is extremely difficult to assign to its proper place in the series, in Alabama at least, for we find in the southeastern part of the Alabama Paleozoic terrane, some of the Knox or Montevallo shales slightly altered into partially crystalline slates, which we have not yet been able to discriminate from the unquestioned Ocoee. It has therefore seemed to us at least possible that the Alabama representatives of the Ocoee of Tennessee may be, in part at least, altered Cambrian shales. In chapter VIII the river alluviums and other formations later than the Carboniferous are mentioned, and it is interesting to find that remnants of the Lafayette, in the form of pebbles and red loam, are to be found in many places in the Coosa Basin at elevations of 100 to 150 feet above the present level of the waters in those regions. These same beds have been traced by the Alabama survey up the Coosa valley to the Georgia line, and they are also to be found extending from the west, for a good many miles within the Alabama line along the Tennessee river.

In chapter IX, dealing with the general physical features of the region, Dr. Spencer directs attention to the ancient character of the streams, and concludes that they long ago reached their base level of erosion, and have since been engaged in widening their valleys. In comparatively modern times (Lafayette), there has been a depression which has allowed the deposition of pebbles and loams at altitudes 80 to 150 feet above the present stream level, and of course a still more recent movement of elevation which has brought the streams to their present position. Probably the most striking memorial of these movements is to be found in the "flatwoods" of the Coosa Valley. This chapter is illustrated by a number of sections. Chapters X to XX