1894.] Geology and Paleontology. 1023 
GEOLOGY AND PALEONTOLOGY. 
Ancient Conglomerates.— The presence of intra-formational 
conglomerates is a not uncommon phenomenon. Dr. Walcott notes 
several localities where this form of conglomerate occurs in Paleozoic 
limestone formations, and describes typical ones found in Vermont and 
New York, Pennsylvania, Virginia and Tennessee. The author de- 
fines this species of conglomerate as one formed within a geological 
formation of material derived from and deposited within that forma- 
tion. As to their origin, he offers the following theory. Low ridges 
or domes of limestone were raised above the sea level and were sub- 
jected to the action of sea shore ice and the aerial agents of erosion. 
In the intervening depressions of these ridges calcareous mud was be- 
ing deposited which was solidified soon after deposition. The material 
forming the conglomerate was transported from the shore line and 
dropped upon the sea bed by floating ice. The facts from which these 
inferences are drawn are given in detail. (Bull. Geol. Soc. Am., Vol. 
5, 1894). 
Subterranean Waters on the Coastal Plain.—N. H. Darton 
has published a brief review of the geological conditions under which 
subterranean waters oceur in the Coastal Plain region of the middle 
Atlantic slope, together with an account of wells bored. He shows 
that the geological relations are favorable to the wide circulation of 
waters at several horizons, and gives the approximate vertical posi- 
tions and general areal distributions of these horizons. In southern 
New Jersey, Delaware and a portion of Maryland, the sand series of 
the Chesapeake formation are the principal water producers. Along 
the western edge of the Coastal Plain from Petersburg to Staten 
Island, the basal members of the Potomac formation yield water at 
moderate depths. The author gives also the “ prospects” in several 
distriets. About Norfolk, water will probably be found on the crys- 
talline floor, 1,500 feet below the surface; in the peninsula region of 
eastern Virginia and Maryland, at the base of the Chesapeake beds at 
depths varying from 100 to 400 feet ; on the eastern shore " of Mary- 
land there are many favorable prospeets, suecessful wells being in - 
operation, drawing their supplies from the Chesapeake, 200 to 300 feet 
below the surface, and from the Pamunkey sands, reached by 350, 440 
and 910 feet boring. (Trans. Am. Inst. Mining Eng., 1894). 
