398 ANNUAL EEPOET SMITHSONIAN INSTITUTION, 1908. 



an attempt is being made to exploit. With the coal, fossil plants 

 were found by Fuchs. This is an important addition to our knowl- 

 edge of the distribution of the Carboniferous because of the geo- 

 graphic position of the area. 



Steinmann (1904) reported the finding of a few characteristic 

 Carboniferous fossils southeast of Tarnia. 



The Carboniferous in Bolivia, especially in the region of Lake 

 Titicaca, was studied by Dereims (1906), Avho describes the formation 

 as composed of sandstones and shales, with a bed of dark limestone at 

 the base and with coal beds. He investigated the coal four leagues 

 north of Mocomoco, at Ococoya and Calacala, where it does not 

 exceed 80 centimeters and consists largely of shale impregnated with 

 carbonaceous matter and is not workable. In the peninsula of Copo- 

 cabaiia, near Yamupata, he saw thin beds of coal, which have for- 

 merly been worked, but the coal is mixed with shale and contains so 

 much sulphur that it can not be used. He states that on the island 

 of Titicaca it is of the same general character. His conclusion in 

 regard to the Carboniferous in Bolivia is that it is the lower or 

 Dimantian stage, and is everywhere marine and contains no workable 

 or good coal. 



PERMIAN. 



The Permian is not known to be present in Peruvian territory. 

 Certain sandstones in Bolivia which extend into southern Peru in 

 the Titicaca region were early classed as Permian or Triassic by 

 Forbes because of their resemblance to the typical Permian of Russia 

 described by Murchison. Forbes, however, states that no fossils hav- 

 ing been found, the age of the beds is a question for inquiry. The 

 formation contains salt and gypsum beds and native copper, the 

 celebrated mines of Cora-Cora being found in them. 



Steinmann (1906) has discussed the Cora-Cora copper deposits and 

 has given the name Puca sandstone to the formation in which they 

 are found. He says that the formation comprises the youngest ma- 

 rine sediments in Bolivia and has a thickness of more than 1,000 

 meters. By the finding of fossils near Potosi, in southern Bolivia,'* 

 in related formations a higher age than Jura is indicated, and accord- 

 ingly he assigns them to the Cretaceous. 



Dereims (1906) says that at Santa Lucia, near Potosi, he found 

 reddish sandstones and reddish gypsiferous shales with some beds 

 that are calcareous, which are of Permian age. The calcareous bed is 

 full of Chemnitzia potosensis, first described by d'Orbigny. He re- 

 marks that d'Orbigny has referred this formation to the Trias on 

 lithologic grounds, but from the fossils it appears that it is Permian- 



°- Compare Steinmann, Hoek, and Y. Bistraus. Zentralblatt fiir Mineralogie 

 etc., 1904, p. 3, zur Geologie des sudosticLeu Boliviens. 



