264 FANNING. 
the northwest. Horizontal bedding is frequently seen, and slight 
folding occasionally occurs. The beds are fossiliferous and have 
been referred to the Miocene. The country has been subjected to 
gentle uplift, and the formations have been elevated without dis- 
turbance and almost without folding. The beds are very soft, 
which shows that there has been no nearby igneous activity to 
metamorphose the strata. 
The formation lies upon the northwest flank of the Zambales 
Range, and the contact with the igneous can be traced along the 
eastern and southern hills. The absence of metamorphism clearly 
shows that the sedimentaries are the younger. The igneous 
undoubtedly represents the Tertiary land mass around which 
the sedimentaries were laid. 
Tuffaceous marls, shales, and clays.—The majority of the sedi- 
mentaries can be classed as tuffaceous marls or clays with vary- 
ing calcareous content. The stone is generally soft, gray, and 
exceedingly fine-grained. Analyses of three specimens are given 
on page 278. 
West of Bani the beds are beautifully exposed and comprise 
the western hills. The formation there has a slight dip north- 
westward to the sea with occasional gentle folding. Some beds 
are so low in calcareous content as to be named a shale or clay, 
and others are so high as to be classed as limestones. All 
appear to be more or less tuffaceous—a feature not visible in the 
hand specimens and unsuspected in the field. However, under 
the microscope, rock fragments were seen, which indicate a 
double origin. ; 
It would seem that the deposition of the sediments, in part 
derived by erosion from the igneous land mass, was accompanied 
by the simultaneous inclusion of tuffaceous material, evidently 
from distant sources. The calcareous nature of the rock is prob- 
ably due to the decomposition, possibly solution and precipitation, 
of the coral reefs which fringed the ancient shore line. Coral 
fragments and calcareous shell fragments are frequently found. 
The following fossils were collected :° 
Natica globosa Chemn. Dentalium tenuistriatum. 
Oliva (ancilla) sp. Arca sp. indet. 
Pleurotoma carinata Gray. Tapes indet. 
Morio echinophora Linn. Septaria arenaria Lam. 
Hindsia dyki Mart. Fusus sp. 
Flabellum sp. Turbo borneensis. 
* Determinations by Warren D. Smith. 
