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Geology of Antigua's First Cycle Antigua has fortunately been visited by a number of geologists, most recently by Earle, whose report, to which a bibliography is appended, furnishes the following details regarding the beveled strata and the probable conditions of their deposition. The physiographic notes here introduced are largely based on my own observations during a ten-day visit, when I received many helpful courtesies from His Excellency the Governor and other officials as well as from Mr. William Forrest, a resident well versed in the geology of the island. The southwestern fourth of the island area exhibits the lowest members of the inclined series, in part lavas but more largely agglomerates, with a total thickness of several thousand feet. A subaerial origin is inferred for the agglomerates because of their irregular bedding. The rocks here seem to be of relatively uniform resistance, for they are dissected chiefly by insequent streams, under the lead of which the volcanic mass has been reduced to subdued mountainous forms with bare outcrops only of small extent. Next follows an additional series of volcanic beds, described by Earle as "waterdeposited and stratified tuffs, volcanic grits and sands, with intercalations of marine and fresh-water chert and limestone" of "local development. . . . There appears to be no very definite junction between the true bedded tuffs and the pseudo-bedded agglomerates and ash beds of the [underlying] volcanic area. . . . At intervals during the deposition of these beds, there must have been long periods unbroken by any volcanic eruptions. This is proved by the existence of beds of marine limestone and chert enclosing the remains of corals which cannot flourish except in waters free from external detritus." These beds include also a number of shallowwater mollusca, "such as Pecten, Lima, Cardium, Turbo, Turritella, Lithodomus, etc." Higher in this series and associated with the volcanic grits is a flint breccia, "made up of silicified fossils--corals, lamellibranchs, algae, etc.," which appear to be almost identical with the fossils of the great series of limestones in the northeastern third of the island, to be described below. Indications of renewed volcanic activity are found in an agglomerate spread out upon the grits. The occurrence of stronger and weaker beds in this part of the series is betrayed by the development of several overlapping cuestas, with their steeper scarps to the southwest and their gentler slopes to the northeast, best seen in the central and southeastern part of this quarter of the island. Inasmuch as the cuestas strengthen to fairly strong relief and weaken to disappearance along their strike, it is inferred that the determining beds are of lens-like form. Above the grits is a series of "lacustrine and freshwater cherts," associated with "impure limestones and marls. The cherts contain a large amount of petrified wood, both monocotyledons and dicotyledons, sometimes a foot in diameter, and abundant fresh-water gasteropods which are sometimes so plentiful as to form a very large proportion of the rock." Some of the chert beds form a rather strong cuesta a few miles in length which rises to good height near the center of the island, where, as it is separated from the submountainous volcanic area by a well defined subsequent valley presumably excavated along a series of weak tuffs, its long-arched crest serves as a delightful belvedere from which a fine prospect is opened in all directions. Weak tuffs of a considerable thickness overlie the cherts and determine the excavation of a medial subsequent lowland, one or two miles in breadth, which crosses the island from coast to coast. Thus several thousand feet of bedded deposits overlie the basal volcanic rocks. Home