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Alvaeo Silveira: Analyse No. 3. Calcareo da pedreira da Capoeira Grande 

 a um kilometro de Barroso. Revista Industrial de Minas-Geraes, Anno I, 

 No. 9, 15 de Junho de 1894, pagina 232. Ouro Preto, 1894. 



Alvaro Astolpho da Silveira : Engenlieiro Ctief e. Relatorio da commissao 

 geographica e geologica. Annexo ao Relatorio apresentado ao Dr. Secre- 

 tario de Estado da Agricultura do Estado de Minas-Geraes pelo Inspector 

 de Terras e Colonizagao em 1897. Annexo A, pages 1-19. Ouro Preto, 1897. 



Spix und Martius : Reise in Brasilien, volume I, page 287; volume II, paga 

 558. Munich, 1823, 1828. 



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 can Institute of Mining Engineers, volumes XIII-XVI. New York, Sep- 

 tember, 1917. 



.1- J. VON TscHUDi: Die Brasilianische Provinz Minas Geraes. Petermann's 

 Mittheilungen, 42 pages, 4°. Gotha, 1862. 



EuGEN Warming : Ein Aufzug nach Brasiliens Bergen, Die Natur., Neue Folge, 

 volume VII, pages 156-159, 170-172, 194-196, 208-209. Halle, 1881. 



EuGEN Warming : Lagoa Santa. Et Bidrag til den biologiske Plantegeografi. 

 Avec resume en frangaise. 336 pages. Kjobenhavn, 1892. 



Horace E. Williams : Notas sobre . . . occorrencia de nickel perto de 

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 Anno V, No. 1, paginas 21-28. Rio de Janeiro, 1916. 



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 Brasiliens Kalkstenshuler af Prof. Lund udgravede Dyre — og menuesbek- 

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PARA 



Previous investigations. — A good resume of the geology of Para is 

 given by Katzer in his Grundziige der Geologie des nnteren Amazonas- 

 gebietes, Leipzig, 1903. I have followed his map in the main, bnt with 

 modifications on certain points. The distribution of the various forma- 

 tions on the southern side of the Amazon, as shown on Katzer's map, is 

 especially uncertain. The Carboniferous has been certainly recognized 

 south of the Amazon in the State of Para only on the Tapajos ; the Silu- 

 rian, Devonian, and Cretaceous have not been certainly recognized in 

 Para on the south side of the Amazon at all. The ages of the rocks of 

 areas so represented must therefore be considered as yet in doubt. The 

 area shown as Carboniferous or Permian about the confluence of Eios 

 Aragua^^a and Tocantins I have shown as Permian, because it thus flts 

 on to the known Permian of Maranhao without doing violence to Katzer's 

 views. The occurrence of Devonian beds on the Araguaya is very doubt- 



