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80° to 82°, and explained how reefs were formed, illustrating 
Whit Sunday Island as an example. 
He further explained how the waste of the reef is ground 
into fine mud, or coralline sand, that the calcareous paste coats 
particles of sand which become cemented around the nucleus, 
and how by the constant roll and agitation of an ever restless 
sea, these physical conditions lead to the production of Oolitic 
limestones, which are found around the shores of coral islands 
of our own time. Having thus established the fact that Oolitic 
limestones are produced under the conditions just described, he 
proceeded to give an explanation of the genesis of the Oolitic 
rocks. He said the Oolitic series of rocks may be described 
generally as a succession of argillaceous deposits, as the Oxford 
Clay and Kimmeridge Clay, with interposed beds of rock, such 
as the Inferior Oolite, the Coralline Oolite, and the Portland 
series; that the Coralline theory applied only to the Oolitic 
limestones, for the argillaceous deposits have clearly been formed 
under other conditons. Nearly all the Oolitic limestones con- 
tain Coral structures more or less extensive; in the Inferior 
Oolite were three distinct reefs super-imposed on each other, 
having intermediate beds of Oolitic rock; the Great Oolite had 
its reef, the Coral Rag possessed its reef, and the Portland Beds 
contained zoophytic productions in like manner. He then 
shewed a mass of Coral in confirmation, and said that was the 
roe-stone or Oolitic rock which rested upon the reef. He sub- 
mitted that it was neither more nor less than a portion of the 
wasted reef which had been broken and triturated and ground 
into mud; that the paste had coated particles of sand, and the 
whole had been cemented by the calcareous waters, and formed 
into the rock we call Oolitic Limestone. For all these granules 
had a nucleus, and the calcareous globule was made up of a 
succession of lamin, as may readily be seen in thin sections of 
the rock prepared for the microscope. So the genesis of the 
Oolitic rocks was due to the vital energies of the zoophytes that 
lived in the Jurassic seas. The reefs that remained were mere 
fragments of those which had once existed, and the reefs that 
had disappeared had furnished the materials out of which the 
Oolites had been constructed. 
