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of those which remained, an estimate of the thicknesses of these forma- 
tions without more detailed study is an extremely difficult one. This 
shale may have had any thickness between 100 and 1,000 feet. Minute 
lenticular seams of lignite and pieces of resin are occasionally seen therein. 
A limestone, also of unknown thickness, lies above this sandy shale, and 
again, over the latter, a sandstone, but owing to limited time, no close 
investigation of the formations lying much above the shale horizon was 
made. 
The fossils shown by Plate III were collected by the writer from the 
shale in the Loboo River; those on Plate IV by Mr. Weber, of Batangas, 
from the limestone, just above the latter, on the same stream. This 
limestone is of a dirty, cream color; it resembles some horizons in Cebu 
and occurs in rather thin, fissile beds. 
A great thickness of most interesting deposits rests unconformably 
above these typically marine sediments. These, in all probability, are 
of yoleanico-marine origin. The rock in this region is called dhobie by 
the American prospector, probably because he confuses it with the adobe 
from the western part of the United States, with which, however, it must 
not be confounded. The latter is generally an alluvial deposit derived 
from weathered basic igneous rocks, whereas the former for the most 
part is a tuff of volcanic origin, which has been blown out and deposited 
either in the sea or lagoons. Stratification is very pronounced in this 
Batangas deposit, which is not the case with the adobe of the Western 
States of America. However, the chief difference is to be found in the 
heterogeneous physical and mineralogical aspect of the former, yet the 
writer does not assert that there is no true adobe in this district; in fact, 
in the northern part, in the neighborhood of Mount Maquiling it occurs 
typically. 
These tuff deposits exhibit very different facies throughout their great 
extent. In some localities they show a distinct stratification, while 
distant only a few feet, no sign of this can be seen. One stratum may 
be composed of extremely fine silt, with the layers above and below dis- 
tinctly constituting a tuff which contains both fine and coarse materials, 
Fragments of pumice, obsidian, and round concretions of fine clay 
(lapilli) all may be encountered in one exposure. 
A series of eight samples collected from an exposure near the city of 
Batangas by Mr. George Weeden, of that city, shows the variations in 
these deposits exceptionally well. All of these samples occurred in layers 
varying from 6 inches to several feet in thickness and cliffs of from 50 
to 100 feet in height, and entirely composed of No. 7, have been seen. 
The following is a brief summary of the lithological characters of the 
several beds, given in order from above downward : 
No. 1: Fine grained, almost a mud, but slightly vesicular, and possessing dis- 
tinct stratification. Color, gray. Dark specks, which are minute fragments of 
voleanic glass, are occasionally seen. It parts readily along the bedding plane. 
