Waring: Geology of Northeastern Brazil. 207 



Angico and Carnahyba is largely covered with a thin layer of desert 

 limestone, but at Angico and at Jurema small exposures of gneiss show 

 general northward strike and nearly vertical dip. At Carnahyba a 

 poor exposure of the gneiss seems to have its foliation planes striking 

 west. Between Carnahyba and Joazeiro granite appears. On a small 

 island in the river near Joazeiro, and on the opposite shore, a dark 

 crystalline rock of granitic texture is well exposed. 



From Bom Fim and Queimadas excursions were made in the basin 

 of Rio Itapicuru, and the strike of the gneiss wherever observed was 

 found to be conformable with the north-south trend of the serras of 

 Itiuba and Jacobina. 



Serra da Itiuba is a granitic range, rising two hundred to three 

 hundred meters above the surrounding country. Much of the ma- 

 terial composing it exhibits gneissic banding, but the core of the 

 range seems to be of massive granite. Where the main drainage 

 divide was crossed two kilometers west of Caldeirao de Vaca it is a 

 red granite. East of the range there is also some granite, the most 

 prominent exposure being at Pedra Vermelha, where a bare, rounded 

 mass, one hundred by three hundred and fifty meters, trending N. 15° 

 E., rises twenty-five meters above the plain. At its west base there 

 is perennial water in a small, undrained area, deeply filled with soil 

 in which fossil bones are found. Among specimens obtained by the 

 writer were several teeth, one of which was pronounced by Dr. W. J. 

 Holland, of the Carnegie Museum, Pittsburgh, to be the tooth of a 

 horse, another the fragment of a tooth of a mastodon, and another to 

 be a molar of Toxodon Burmeisteri, which had not been reported from 

 so far north in Brazil. ^^ Other specimens sent to Dr. Holland have 

 been examined by him, and as an appendix to this paper he gives a 

 list of this material. (Cf. p. 224.) 



The presence of fossil bones in a similar marsh at Lagoa da Lagea, 

 three hundred kilometers to the northeast, has been noted by Dr. 

 Branner.-*' 



One feature of the granitic gneiss in the vicinity of Caldeirao 

 Grande, southwest of Serra da Itiuba, is the presence of holes, like 



^^ W. J. Holland, To the River Plate and Back, G. P. Putnam's Sons, New York, 

 1913. P- 210. 



-^ On the Occurrence of Fossil Remains of Mammals in the Interior of the Stales of 

 Pernambuco and Alagoas, Brazil, by John C. Branner, Am. Jour. Sci., Feb., 1902, 

 PP- 133-137- 



