174 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4th Ser. 



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carry numerous impressions of ammonites, oysters, and in- 

 ocerami, which are of forms referable to the Taylor or Austin 

 horizons of the Texas section. These beds underlie the 

 shales of the eastern side of the river. The greater portion 

 of the Salado Valley is filled with a heavy bed of conglom- 

 erate, but from near Santa Rita southeastward to Reparo 

 Creek near Rodriguez, a distance of over 25 miles, there are 

 numerous exposures of heavy beds of greenish-yellow sandy 

 clay, which may be the base of the Escondido, overlying 

 a series of blue clays, blue shales and black shales, with 

 indurated bands. These latter clays are laminated and mas- 

 sive, carry more or less selenite, some calcite and barite, and 

 in places boulders of a yellowish brown hard flinty sand- 

 stone. No fossils were found in them, but they are the direct 

 stratigraphic continuation of the beds we have called Papagal- 

 los. These rest upon the San Juan beds. 



The Escondido with Ostrea cortex appears on Camaron 

 Creek about midway between the San Antonio Hills and 

 Ceja Madre and in the western slope of the Ceja Madre we 

 find the brown and blue shaly clay and marls of the Midway 

 with Venericardia alticostata, etc. 



Reparo Creek joins the Salado River just west of Rod- 

 riguez. Half a mile above the junction of the streams, we 

 have a section showing a contact in which the yellowish 

 brown shaly clay of the Wilcox rests on the blue Papagallos 

 shales of the Cretaceous, while further up the creek we find 

 the fine-grained brown and gray sandstones of the Carrizo 

 in contact with the Cretaceous shales at several places. This 

 indicates the transgression of both the Wilcox and the Carrizo 

 over the Midway in this locality. From Rodriguez the out- 

 crop of the blue shale continues down the west side of the 

 Salado River to within a few miles of San Jose and then 

 turns southward, crossing the Sabinas west of Piedras Pintas. 

 At Vallecillo we have the San Juan limestones with Inocerami 

 followed to the east by the Papagallos shale and this by the 

 Midway (?) at Piedras Pintas. From here the line of con- 

 tact runs south to a point three miles east of Cerralvo where 

 there is a range of hills with eastward facing scarp and north- 

 east dip. They have a height of 200 feet and are made up 

 of the blue and yellow shales of the Papagallos which show 



