22 Proceedings of the Royal Physical Society. 
deposits which lie discordantly on the truncated edges of 
the “Scotland” beds. These so-called “oceanic deposits,” 
speaking generally, consist of— 
(a) Chalky limestones, composed of the tests of Foramini- 
fera, and representing the “ Globigerina ooze” of our modern 
oceans, 
(b) Siliceous earths (“ Barbados earth”), composed of the 
tests of Radiolarians and Diatoms, together with Sponge- 
spicules, associated with bands of volcanic ashes. This 
series—as fully admitted by Heckel—is in all respects 
comparable with the “Radiolarian muds” of our modern 
deep seas. 
(c) A second series of Foraminiferal limestones. 
(d) Very finely levigated clays, coloured, mottled, or 
white, which represent the “red clays” of the abysses of 
our existing oceans. 
At the close of the deposition of the “ Oceanic series” just 
described, elevation again set in, the newly formed deposits 
undergoing denudation in the process. Progressive elevation 
of the sea-floor continued till a depth of thirty to forty 
fathoms was reached, when reef-building corals began to 
flourish, and the conditions must for a time have been 
sufficiently stable to allow of the formation of extensive 
coral-reefs. Elevation again set in, however, and the reefs 
were ultimately raised to a height of about 1000 feet above 
the present sea-level; thus forming a capping of coralline 
limestones, resting wnconformably upon the “ Oceanic series ” 
to a thickness of 150 to 200 feet over about six-sevenths of 
the entire area of the island. This final elevation undoubtedly 
took place in the Pleistocene period. 
The sequence of events indicated by the successive deposits 
of Barbados is too clear to admit of misinterpretation. 
Beyond reasonable doubt, the “Oceanic deposits” are a series 
of deep-sea muds, in all essential respects comparable with 
the Globigerina mud, the Radiolarian ooze, and the abyssal 
clays of our existing deep seas. They were probably laid 
down in water of at least 2000 fathoms in depth. This con- 
clusion is not only supported by the characters of the 
Radiolarians, as elucidated by Heckel, but is further borne 
