SERRA DO ESPINHAQO, BRAZIL 389 



Joazeiro and close to the Sao Francisco, and which he informs me 

 .s composed of horizontal beds of sandstone and conglomerate over- 

 lying inclined quartzite. The topographical features and the eleva- 

 tion of this ridge, as of others in the vicinity, are suggestive of the 

 Cretaceous plateaus of the lower Sao Francisco and of the states of 

 Ceara and Piauhy, and there is nothing improbable in the hypothesis 

 that these (coming from Piauhy) extend into this region. This hypo- 

 thesis would become a certainty if one could accept unreservedly the 

 statement of M. Liais (21) that at a place called Engenho, some- 

 where near the western base of the Jacobina serra, he found nodules 

 of argillaceous limestone containing scales of Lepidotus, a ganoid 

 tooth, and gasteropod shells which he identified as Paludina 

 and Planorhis. These fossils, with the exception of the shells, are 



Fig. 9. — Serra do Encaibro (Ridge Pole), seen from the river Sao Francisco. 



very suggestive of those of the fish-bed of Ceara, which have been 

 carried far and wide over the country, and in part probably over 

 this very road. On the other hand, experience elsewhere has shown 

 that the statement of this author must be taken with caution. Still 

 there is no inherent improbability in the hypothesis that the fossils 

 may have been found in situ as stated. 



In the region to the west of the serra Mr. Allen seems to have 

 generalized his observations on inclined limestones to all of those seen 

 along the road. It is certain that horizontal beds of limestone like 

 that above mentioned in the vicinity of Joazeiro occurs at and about 

 Chique-Chique, and, as in other parts of the Sao Francisco basin, 

 it is probable that both horizontal and inclined limestones occur 

 among the older rocks. The chert-strewn hills are suggestive of the 

 series to the east of the serra in the Paraguassii basin. 



Another line of travel across the Serra do Espinhajo region in the 

 state of Bahia lies to the southward of the Paraguassu route above 

 described, and passes by Maracas, Sincora, Villa do Rio de Contas^ 

 Caetite, and Monte Alto, to Caranhanha on the river Sao Francisco. 



