62 DR. H. B. GUPPY. 
The Presipent, Sir Grorce Gasrien Stoxes, Bart., D.C.L., P.R.S., 
iu the chair :—I am sure all will agree in according a vote of 
thanks to Dr. Guppy for his paper (applause). I will now ask 
those present who have made the subject their study to give the 
meeting the advantage of their views. 
Captain W. J. L. Waarron, R.N., F.R.S., Hydrographer to the 
Admiralty.—It has afforded me great pleasure to hear Dr. Guppy’s 
most excellent paper. In it he has given us a very good abstract 
of the condition of affairs as regards our knowledge of coral 
reefs and their growth. It is rather presumptuous in me to offer an 
opinion, because I do not pretend to a mastery of the different 
branches of scientific knowledge which are requisite adequately to 
deal with the question of coral growth, but I have taken great 
interest in it, and have seen a great deal of coral reef in my time, 
and have formed my own ideas as to their formation. Speaking 
generally, lagree with Dr. Guppy, although on one point towards the 
end of his paper—to which I shall refer presently —I do not quite con- 
cur with him. In the early part of his paper he mentions the question 
of the growth of coral. A fact has recently come to my knowledge, 
—at least I believe it to be a fact,—and that is that at the Keeling 
islands, which Mr. Darwin examined, a part of the rim of the reef, 
which was submerged at the time the survey was made, is now above 
water. The depth of water over it in 1831 was eighteen feet. . I 
have this information from a gentleman who knows the island, and 
who has lived there all his life.—Mr. Ross. I have written out to 
him to ask his opinion as to what has been the cause of this,— 
whether it is a growth of the coral reef itself or an upheaval; and, 
until we get that definite information, perhaps my observations may 
seem rather premature, because we cannot deduce much from what 
we are not quite sure of. Dr. Guppy mentioned the antiquity of 
coral reefs. There is one experience of my own which impressed me 
more than anything else with the great antiquity, not only of these 
reefs, but of the world in general, and that was an examination of 
the island of Aldabra, in the Indian Ocean. This is an upraised 
atoll about twenty feet high, which, from the steepness of the sub- 
marine slope outside, could never have been much larger, though it 
has been worn away on the outside by the action of the sea for some 
150 or 200 yards, and is being slowly but surely disintegrated on the 
inside by the action of the mangroves which grow in the lagoon. In 
this small island there still exist gigantic tortoises of a species very 
distinct from those in other islands of the Indian Ocean. To form 
