30 



material will lose a large part or the whole of its value ; 

 for, like the brief notes of a field note-book, their whole 

 significance can only be understood by the one who made 

 them. 



" Besides the work of preparing and arranging the 

 collections, the work of the Commission, during the 

 latter half of the year 1877-78, has been as follows: — 

 Besides the general direction of the work of my assist- 

 ants, I have devoted myself to the preparation of a long 

 report on the Geology and Physical Geography of the 

 Lower Amazonas, embracing all my work previous 

 to the establishment of the Commission, together with 

 the studies in the service of the Commission of Messrs. 

 Derby, Freitas, Smith and Penna. This report, illus- 

 trated by numerous maps and drawings, is to be followed 

 by extended papers by Messrs. Derby and Rathbun, 

 describing the whole of the fossils of the Silurian, Devo- 

 nian, and Carboniferous of the Amazonas. This report, 

 prepared in English, and forming in itself a large volume, 

 is nearly translated, and will be ready to be submitted in a 

 little more than a month, and it will be found to be the 

 most important contribution ever made to South American 

 geology. I have pressed the preparation ot this work, 

 not only on account of its immediate scientific import- 

 ance, but because our facilities for its preparation were 

 greater than for that of any other. I have carried for- 

 ward to greater or less completion several works on the 

 reefs and harbors of the coast north of Rio, and an 

 extended memoir on the archaeological collections of the 

 Commission, and the " sambaquis " of the coast. Recently 

 I have been at work on the Geology and Physical Geog- 

 raphy of the Provinces of Pernambuco, Alagoas, Sergipe, 

 and Bahia, including the lower Ssio Francisco, discussing 

 the question of the sccca in those provinces. This volu- 

 minous report will require yet some time for its com- 

 pletion. Mr. Derby has occupied himself almost exclu- 

 sively with his Amazonian work, geological and palas- 

 ontological, and his explorations in Bahia and Sergipe. 

 About two months ago, as he was suffering from fever 



