100 Duncan— Miocene Beds of Antigua and Malta. 
San Domingo, Owyhee, and Isle de Bourbon do now-a-days. 
The period of rest was a time of wear and tear for the future 
chert, and it was exposed to all the rapid destructive agencies 
of the tropics. A change in the general physical geography 
of a large area, of which Antigua formed a part, occurred 
before the next subsidence, for the coral-growth which then 
commenced was luxuriant in the extreme, and wood and land- 
shells more rarely drifted on to the reef. The new coral-reef 
grew at first from the supporting rock, lower down than the 
elevated chert, and the marl is now found below that older 
reef: as subsidence took place, the chert began to support the 
new coral-reef; as it progressed, the chert became covered, and 
growth commenced at the side of the inclined strata; and, 
finally, as the island sank hundreds of feet, the future marl 
collected. 
The last changes were the gradual upheaval of the marl 
associated with all the older beds and the original trap-rocks,— 
its denudation to a great extent,—and a great alteration in the 
physical geography, fauna, and flora of the region. 
It is hardly possible to connect these oscillations of level 
with those which have occurred in the other West Indian 
Islands; for, owing to the insular position and the local cha- 
racter of many of the disturbances of level, the ordinary rules 
of stratigraphy fail. There are inclined Tertiary strata in 
Jamaica and in Trinidad; but the strata which have excited 
attention in San Domingo are not inclined; but, like the An- 
tiguan Chert and Marl, have been simply elevated en masse 
with the supporting mountain. The establishment of the West 
Indian equivalents of the Antiguan strata can, then, be but 
slightly assisted by stratigraphy alone. 
Palzxontological evidence, however, has been adduced which 
determines that general correlation between the limestones and 
shales which has been already noticed. They have all been 
decided to be of Mid-tertiary age; but as yet the equivalency 
or parallelism of the inclined strata of Antigua with the lowest 
of the Mid-tertiaries of Jamaica, and with the Nivajé Shale of 
San Domingo, can no more be asserted than that of the Anti- 
guan Chert, the inclined Jamaican limestones, and the limestone 
(erroneously called ‘ tufaceous’) of San Domingo. Further re- 
searches are required before these important matters can be 
determined. The immense distance between the West-Indian 
and Kuropean Mid-tertiary strata must leave serial relation- 
ship and paleontology alone to produce evidence concerning 
their approximate contemporaneity. In only one instance 
has an Eocene formation been asserted to exist in the An- 
