Hartt.] 360 [April 17, 



port on the Geology and Physical Geography of the Lower Araa- 

 zonas, embracing all my work previous to the establishment of the 

 Commission, together with the studies in the service of the Commis- 

 sion 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, Devonian, and Carboniferous of the Amazonas. 

 This report, prepared in English, and forming in itself a large vol- 

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

 more than a month, and it will be found ta be the most important 

 contribution, ever made to South American geology. I have pressed 

 the preparation of this work, not only on account of its immediate 

 scientific importance, but because our facilities for its preparation 

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

 cently I have been at work on the Geology and Physical Geography 

 of the provinces of Pernambuco, Alagoas, Sergipe, and Bahia, in- 

 cluding the lower Sao Francisco, discussing the question of the secca 

 in those provinces. This voluminous report will require yet some 

 time for its completion. Mr. Derby has occupied himself almost ex- 

 clusively with his Amazonian work, geological and palaeontological, 

 and his explorations in Bahia and Sergipe. About two months ago, 

 as he was suffering from fever contracted on the Amazonas, I sent 

 him to Sao Paulo where he made, especially in the Soroeaba district, 

 a valuable series of observations confirmatory of, and additional to, 

 those of Mr. Rathbun. This last assistant has prepared an extended 

 report of his excursion to Sao Paulo, giving the first intelligible de- 

 tailed account of the geology of that province. He has finished his 

 work on the geology of Bahia, on the coral reefs of that bay, and has 

 concluded the corals and radiates collected by the Commission, which 

 he has illustrated by a splendid series of photographs by his own 

 hand, which is not equalled by any similar work that I have ever 

 seen. I have already alluded to his studies of the Amazonian fossils. 

 Mr. Branner has been busily engaged in the preparation and mount- 

 ing of the Cretaceous fossils collected by Dr. Freitas and himself, in 

 the provinces of Sergipe and Pernambuco, and in the preparation of 

 a series of reports on the island of Fernando de Noronha, on the 

 reefs of the north coast, and on a journey made by him to the inte- 

 rior of the province of Pernambuco, etc. 



