viii, a, 4 Smith: Fossil Invertebrate Fauna 245 



Cherts. — In Ilocos Norte, Pangasinan, Balabac, Panay, and 

 other localities there are outcrops of hard, red cherts or jaspers, 

 in some places as hard structureless bowlders, and in others as 

 fissile beds. When I first found these in Ilocos Norte, I compared 

 them with the cherts of California. 11 On examination with a 

 microscope they were found to contain fragments of radiolarian 

 tests. These rocks have a wide distribution in this part of 

 the world, and have been provisionally assigned to the Jurassic 

 by Martin. 12 



Table II is a provisional table of Philippine stratigraphy 

 revised from similar ones which have appeared in my earlier 

 papers. This gives the vertical distribution, as near as we now 

 know it, of the various sedimentary formations and their rela- 

 tions to the different igneous rocks. 



It is my opinion that while some of the coal measures belong 

 to the Eocene, most of the coal seams occur in the Miocene, 

 particularly the uppermost and the poorer seams such as the 

 East Batan. 



Old "slates" and other rocks. — Masses of indurated sediments 

 almost slaty in character are found in certain islands and are 

 pretty certainly older than the Tertiary. 



Abella called attention to these in Misamis, Mindanao, and near 

 O'Donnell, Luzon. 13 



In a report made in 1900, Becker 14 wrote as follows : 



* * * If such strata exist, it may be that they are so folded 

 up with the greatly disturbed Eocene that they have not hitherto been 

 differentiated. From the descriptions of Surigao and Misamis, it would 

 seem, too, that considerable areas of slate are there exposed and that 

 portions of these rocks are not highly metamorphosed. This region may 

 possibly yield fossils. In carrying on geological investigations in the 

 Philippine Islands, the indications afforded by the constitution of neighboring 

 islands should evidently be borne in mind, for if the similarities which might 

 be expected do not manifest themselves, the cause of difference demands 

 elucidation. 



Ferguson 1B describes from the Island of Masbate a series 

 of alate-like rocks on Kaal Creek. Some of these slate rocks are 

 reddish, containing psilomelane lenses; other portions are 

 darker and invariably lined with a minute network of quartz 

 and calcite veins. 



"■This Journal, Sec. A (1907), 2, 235-253. 



" Reisen in den Molukken. Leiden (1903), pt. 3. 



u Manantiales Minerales de Filipinas. Manila (1893), 144. 



"Op. tit., 547. 



" This Journal, Sec. A (1911), 6, 404, 405. 



