446 JENKINS— GEOLOGY OF THE [May 29. 



stones are all obviously in the same horizon. Although each locality 

 seems to have its own specific character and fossils, yet they all are 

 more or less similar and are probably dififerent facies of the same 

 horizon. 



Itapasaroca. 



Half a kilometer beyond Itapasaroca, at kilometer 45, the rail- 

 road cuts through beds of limestone. This cut exposes four or five 

 meters of the series. In the material thrown out of the cut, impres- 

 sions of shells are abundant. In some of the rocks figures of plants, 

 such as palms, occur. No good fossils could be found, but there 

 is an abundance of material. The rock is a light or buff color. It 

 occurs in beds of a foot or six inches in thickness. The strata 

 stands almost horizontal or dipping slightly towards the sea to the 

 southeast. In this exposure some of the beds have been slightly 

 compressed into waves of about a meter in height. Beyond this cut 

 is the old valley of Ceara-Mirim, and on its opposite side are the 

 crystalline rocks, at a lower level than the limestones. 



Ccard-Mirim. 



About two hundred meters up the railroad from kilometer 35, 

 near the town of Ceara-Mirim, a lime kiln is situated on the south 

 side of the railroad track. One hundred meters or so up the hill 

 from this is a limestone quarry. The hill forms the bank of the 

 valley of Rio Ceara-Mirim, and the railroad skirts its edge. The 

 beds at the quarry are practically horizontal, four meters being 

 exposed in the cut which lies about 28 meters above the railroad 

 track, whose elevation at Ceara-Mirim station, not far off, is 31.5 

 meters. Thus these beds lie about 60 meters above sea level. The 

 material of the beds is very hard and limy. The fossils, which 

 formerly must have been in this rock, have been completely obliter- 

 ated by circulating waters. It was noticed at this quarry that the 

 decomposition of the beds was aided by the action of roots of the 

 shrubs, which opened cracks in the limestone allowing surface waters 

 to pass readily downward. These waters carry with them iron 

 from the sandstones above and deposit it in the cracks, leaving the 



