114 The Amefican Geologist. August, 1904. 
yon). Here he gives the thickness at 800 feet. The section 
along the canyon is ahnost directly across the strata, which 
dips uniformly at a moderate angle. It shows an unconform- 
ity near the top and another at the inner end of the canyon, 
and a little beyond there is a fault; above which I measured 
the thickness and found it to be 1700 feet, and if the beds are 
not repeated at the fault, it was estimated that several hundred 
feet more would have to be added.''= This correction is im- 
portant, as it shows that the limestones here have about the 
same development as is now known to obtain in southern Flor- 
ida on one side and in Jamaica on the other; and it throws 
more light on the amount of denudation of the neighboring 
hills. Furthermore, the discrepancy in his measurement does 
not strengthen the value of INIr. Hill's undigested opinion, as 
above pointed out. 
As expressed in the beginning of paragraph Xo. 3, I could 
not object to Dr. Dall's dissent from my conclusions (though 
I should prefer him to accept them), provided he had at- 
tempted to show some other feasible explanation of the phe- 
nomena, which he says he is "convinced that they admit" of. 
In the latter part of paragraph 3 and in No. 4 Dr. Dall cites 
evidence that Jamaica and Cuba have not been entirely sub- 
merged m later geological days. The introduction of this 
topic has no bearing upon my hypothesis, and its treatment 
is liable to leave the impression that here is a strong point 
against mv conclusions. The same infelicitous treatment is a 
prominent feature of other paragraphs. In Cuba, the terraces 
and sea caves at about 400, 700 and 1000- 11 00 feet suggest 
that Central Cuba was so submerged as to be represented by 
only a few small islands, though Dr. Dall fails to use such 
evidence of partial submergence in his paragraph 5. It ma}^ 
be added that these recent terraces could not date to the orig- 
inal uplift of the limestones, which even near by in places have 
been entirely denuded away. 
With the cited correlations of Mr. A'aughan (in paragraph 
6), I know of no reason to dissent, but when the heights of the 
coral reefs are mentioned as occurring to only 40 feet, the one 
inference to be drawn is that this slight change of level is all 
that is recorded, while in reality living species of mollusks oc- 
* "Geoloirical Evohi'ion i>f Cuba," cited before, page 76. 
