Yol. 63.] THE CORAL-ROCKS OF BARBADOS. 335 



by Prof. Spencer as < pockets rich in corals ' {op. jam cit. p. 359), 

 occur. In these cuttings, no matter whether the terrace-escarp- 

 ments which they traverse are at high or at low levels, the corals 

 are invariably of the same character, being massive reef-corals 

 similar to those at present growing on the outer faces of the sub- 

 marine terraces which extend along the southern and western 

 coasts of the island. Par from being ' pockets' of corals, these rich 

 deposits are the normal formations characteristic of the outer and 

 upper slopes of coral-limestone-reefs. 



It is necessary, while studying the structure of raised coral-reefs, 

 to bear in mind that the massive reef-corals resist the solvent action 

 of percolating waters far better than do the branching corals and the 

 mollusca which mainly comprise the fauna of the shallow lagoons, 

 bays, and channels lying behind the reefs proper. I obtained very 

 plain evidence of the resisting power of the reef-corals in the lime- 

 stones at Golden Ridge, about 900 feet above the sea-level. Here 

 the reef-corals are seen surrounded and covered by the red decom- 

 position-products of the limestone. Every trace of branching corals, 

 of mollusca, and of calcareous sand has disappeared, but the massive 

 reef-corals are still in excellent preservation. 



About 4 miles north of Bridgetown, near the 400-foot contour, I 

 detected dipping-beds inclined to the south-east at about 10° in 

 Cane-Garden Gully. About a mile eastward, in Jack-in-Box and 

 Prout's Gullies, at an altitude of about 500 feet, dipping-beds also 

 occur. At the former place, towards the south-west of the section, 

 the upper beds dip at 7° south-south-westward, while the lower 

 dip in the same direction at about 3°. At the north of the 

 north-eastern part of the section both the upper and the lower beds 

 are horizontal, while towards the south the lower beds gradually 

 assume an inclination to the south-south-east until they dip at 30°, 

 the upper beds remaining practically horizontal. At Prout's Gully 

 on its southern side the upper beds are horizontal, while the lower 

 dip north-north-eastward at from 8° to 10°. On the northern side 

 the beds everywhere are either horizontal, or slope to the north- 

 north-east at 1° or 2°. In numerous other sections in this district 

 the limestone lies in the same manner as it does on the northern 

 side of Prout's Gully. 



In a distance of rather less than 2 miles from Cane Garden the 

 road traverses the escarpments of the 400-, 600-, 700-, and 800-foot 

 terraces. The beds seen are of rubbly limestone, and are practically 

 horizontal, although in places signs of current-bedding may be 

 detected. In the road-sections near Porey's Spring, at the base of 

 the 800-foot escarpment, the limestone-rocks are seen resting upon 

 beds of the Oceanic Series. North of the spring the coral-rocks 

 slope at about 2° southward ; while, in the sections on the road 

 south of the spring, the limestone-beds dip at 3° to 4° south-south- 

 westward, and overlie red clays of the Oceanic Series. 



