20, 1 Smith: Pidatan Oil Field, Cotabato, Mindanao 31 
the one which we shall call the Banisilan formation. This con- 
sists of coarse sandstones and interbedded shales, which the writ- 
er considers to be in part of fresh-water origin, since they con- 
tain fragments of wood and impressions of grass and reeds. This 
formation lies nearly flat in the vicinity of Banisilan, with a slight 
dip, not over 2°, however, to the southwest. In Malitabug River 
(Plate 2, fig. 1) a few kilometers south of Banisilan, are almost 
flat-lying loose shales belonging to this formation, but differing 
in lithology from those of the type locality near Banisilan. 
From collections made in other localities by Mr. Moody and de- 
termined by Dr. R. E. Dickerson it seems that this formation was 
deposited in an embayment of the sea where leaves and grass 
stems were occasionally washed in. A good fauna was obtained 
by Mr. Moody from near Matinao about which Doctor Dickerson 
has kindly furnished the following notes: 
The following species were collected from the Banisilan formation by 
Graham B. Moody at his locality 424 which he described as being 1.6 
kilometers east of Matinao, and 0.6 kilometer west of Malitabug River, 
Cotabato, Mindanao: 
List of species from Moody’s locality 424. 
GASTEROPODA 
Calliostoma sp. Nassa crenulata Bruguiere. 
Cancellaria oblonga Sowerby. Nassa. 
Capulus sp. _ Natica albumen Lamarck. 
Cerithidea sp. Natica mamilla Lamarck. 
Conus sp., large. Natica spadicea Reeve. 
Conus lividus Hwass. Pustularia nucleus Linnezus. 
Conus insculptus Kiener. Ranella subgranosa Beck. 
Cypraea erosa Linnzus. Ranella sp. 
Cypraea sp. Sigaretus eximius Reeve. 
Distortio clathrata Lamarck. Triton clavator Lamarck. 
Dolium sp. Turris flavidula Lamarck var. 
Eulima sp. sonde K. Martin. 
Murex cf. pliciferas Sowerby. Terebra. 
PELECYPODA 
Leiconcha trimaculata (Des- 
Arca cf. barbata Linneus. 
Arca cornea Reeve. hayes). 
Cardita antiquata Linnzus. Lima sp. 
Lucina sp. 
Cardita pica Reeve. Macoma nobilis Hanley. 
Chama — Ostrea sp., a. 
Cardium unicolor Sowerby. Ostrea sp., b. 
Chione sp. Pecten squamosa Gmelin. 
Corbula sp. Pecten sp. 
Glycimeris angulatus Lamarck. Spondylus sp. 
