GEOLOGIC RECONNAISSANCE IN BAJA CALIFORNIA 1739 
Fossils —The yellow beds contain fossils at various places 
which indicate later Miocene age, Carrizo Creek horizon. Possibly 
the sediments represent a still longer epoch. Fossils collected from 
the prominent limestone bluff at the head of tidewater at the mouth 
of the Arroyo de la Purisima were determined as follows by Dr. 
Julia A. Gardner, of the United States Geological Survey: Scutella 
Fic. 19.—La Purisima from the south. Pilon in center is Mesa sandstone capped 
by basalt; slopes of yellow beds below. Lava-capped mesas in the distance. 
Fic. 20.—Conglomerates, agglomerates, tuffs, and igneous flows near San Miguel, 
fifty miles northeast of La Purisima, Baja California. 
gabbi Remond: Terebra sp., cf. T. simplex Carpenter; Conus sp., 
cf C. vittatus Hwass; Oliva sp. aff. O. angulata Lamarck; Oliva 
n.sp. aff. venulate Lamarck; Phos. sp.; Turritella sp., cf. T. coopers 
Carpenter; Turritella n.sp., cl. T. ocoyana Conrad; Turritella 
n.sp. aff. T. goniostoma Valenciennes; Turritella sp., ci. T. inezcana 
Conrad; Cancellaria n.sp., ci. C. verusta Gabb; Macron merriamt 
Gabb?; Natica pablonesis Clark?; Chlorostoma (Omphalius) sp. 
