Eathbun.] 354 [April 17, 



in the Ministry of Brazil, and before the several departments had 

 been entirely reorganized and the appropriations determined upon. 

 Prof. Hartt died. There was no one to succeed him, and his large 

 collections were placed in the care of the National Museum at Rio 

 de Janeiro. It is expected that steps will be taken by the Brazilian 

 Government at an early date toward publishing the many reports 

 which were finished under the direction of Prof. Hartt. The extent 

 of these and of the work done by the members of the Commission in 

 Rio, from July 1877 to January 1878, can be best understood from 

 the final report of Prof. Hartt, made to the Minister of Agriculture 

 last December, an English translation of which is appended to this 

 paper. 



The following brief account of the state of systematic geology in 

 Brazil, at the time of Prof. Hartt's death, will assist us in under- 

 standing what he had accomplished in that important branch of 

 research since the publication of his book in 1870. The scanty ma- 

 terial on this subject in my possession, necessarily renders this sum- 

 mary very incomplete. 



Eozoic. -— In distribution about as before stated. Every effort was 

 made to find traces of Eozoon, or of other fossils, in the limestones 

 of thi s age, in the provinces of Rio de Janeiro and Sao Paulo, but 

 without success. 



Lower Silurian. — The metamorphic deposits, lying on the south- 

 ern edge of the plateau of Guyana and on the northern edge of that 

 of Brazil, and consisting in large part of gneisses, and also of only 

 partially metamorphosed quartzites, which still show stratification, 

 and wind and wave structure, have been referred doubtfully to the 

 Lower Silurian. To the north of the Amazonas they have been ex- 

 amined on the Trombetas; to the south of the Amazonas, on the Ta- 

 pajos and, doubtfully, on the Tocantins. (Observations by Mr. Derby 

 and others). The gold-bearing rocks of Minas Gerass are probably 

 of this age, as well as the metamorphic series of some of the other 

 provinces. 



Upper Silurian. — Includes the sandstones and shales underlying 

 the Devonian, to the north of the Amazonas, and containing Ar- 

 tliropliycus Harlani, Lingula cuneata', etc. (Derby.) 



Devonian. — The heavy series of sandstones, sandy shales, etc., 

 with an abundance of fossils at localities on the Maecuru and Curu£, 

 (Derby), and at Erere, are equivalent to about the Corniferous and 

 Hamilton groups of New York state. There are higher beds of 





