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1046 
genus Orbitoides (Lepidocyclina).* ‘This limestone is, to my mind, un- 
questionably upper Miocene, equivalent to the Gaj of the Sind, India. 
At one point, in a cutting on the Danao tramroad about two kilometers 
below the old mines, limestone probably containing numulites was found. 
One form I have identified as possibly belonging to the species NV. scabra 
Lam. ‘This limestone appears to be unconformable with and below the 
orbitoidal beds. 
I have serious doubt as to whether Abella is correct in drawing so sharp 
a line between his two limestone series. According to the map accom- 
panying his “Rapid Description of the Island of Cebu” he regards the 
limestone of Cebu as of two distinct ages, Nummulitic-Tertiary Eocene 
and post-Pliocene. The limestone mantle found capping the Cordillera 
and its outlying ranges contains Orbitoides (Lepidocyclina) verbeekt, thus 
being correlated with the upper beds in Masbate, southern and northern 
Luzon, and Formosa. Abella leaves the Miocene and Pliocene entirely 
out of account; furthermore, I do not believe that further study will 
show any stratigraphic break between the Pliocene limestone and the 
living reefs. 
PHLYSIOGRAPHY. 
THE CORDILLERA CENTRAL. 
The Cordillera Central may be said to form the backbone of the island. 
It extends north and south, corresponding to the long axis of Cebu and 
also to one of the main tectonic lines of the Archipelago. Its greatest 
elevation does not in all probability exceed 1,000 meters. No triangula- 
tion has as yet been done in the interior. It is partially wooded and 
almost without inhabitants, the only human beings to be found there are 
scattered bands of ladrones, or pulajanes, as they are locally termed, and 
the Constabulary who hunt them. Wild and almost inaccessible, under- 
lain by igneous rock which does not support a very flourishing flora, a 
region of pronounced relief, it is not very enticing even to the geologist, 
and the native avoids it as he would the plague. (PI. I shows a portion 
of the Cordillera country.) 
Although the total elevation for a mountainous country is not great, 
the relief of central Cebu is exceedingly pronounced. ‘There are two 
reasons for this; the first and chief one being the short, horizontal 
distance to sea level, which enhances the declivity, and the second, the 
scarcity of vegetation. These conditions are favorable for the develop- 
-ment of steep profiles and V-shaped cross sections in the streams. Never- 
theless, outcrops are few and the talus is very heavy on most of the valley 
* Further study, it is expected, will show these forms to be Lepidocyclina 
insule-natalis Jones & Chapman, or closely related to that form from the Mio- 
cene of Christmas Island. 
This note is added later owing to the receipt of some literature and correspond- 
ence from Mr. Chapman after the body of this paper had gone to press.—W. D. 5. 
