BRANNER: THE STONE REEFS OF BRAZIL. 25 
Bahia, Alagoas, Pernambuco, Parahyba do Norte, and Rio Grande do 
Norte, but those alr ady mentioned are enough to show beyond question 
that the coloring is an accident without any evident relation to the age 
of the beds 
The Tertiary beds of the Amazonas. — Fossils supposed to be of Ter- 
tiary age have been described from the upper Amazon region, but the 
age of the beds referred to seems never to have been determined with 
certainty, though they are evidently not older than the Tertiary. As 
long ago as 1854 Foetterle spoke of the lignite beds of Ica, Tabatinga, 
Loreto, and Pebas on the Marañon, which he supposed were of Tertiary 
age.? 
Orton found at Pebas near the southern boundary of Ecuador fossils 
which Gabb says “indicate a marine or perhaps rather a brackish water 
fauna. There is not sufficient, material to warrant an opinion as to the 
geological age of the deposit,” but he thinks they “ point to a very recent 
Gym 3 
Later Mr. Hauxwell made a larger collection at Pebas and at Pichua 
thirty miles below Pebas. This collection was described by Conrad, who 
is doubtful about the age of the beds.* He says that the fauna “may 
have lived in either fresh or brackish water, but it certainly is not of 
marine origin.” The opinions of both Gabb and Conrad show that the 
statement of Orton to the effect that these shells “ may be Miocene ” 5 
Was premature, About the time that Conrad published his article there 
appeared one by Woodward upon a collection from the same region. 
The author of that paper seems to take it for granted that Orton’s 
Opinion of the age of the beds was correct, and says nothing of any 
reason for referring them to the Tertiary. 
In 1872 Hartt published an article upon the so-called Tertiary basin 
of the Marañon, but he never visited the region he was writing about, 
and based what he said upon the papers of Orton, Gabb, and Woodward, 
cd O, Branner. The oil-bearing shales of the coast of Brazil. Trans. Amer. 
Inst. Min, Engs., XXX., р. 537-554. 
2 Franz Foetterle. Die geologische Uebersichtskarte des mittleren Theiles von 
Siid Amerika, р. 20-21. Wien, 1854. 
? W. M. Gabb. Descriptions of fossils from the clay deposits of the Upper 
Amazon. Amer, Journ. Conchology, 1868, IV., p. 197. 
* Т. A. Conrad. Description of new fossil shells of the Upper Amazon. Amer. 
Journ. Conchology, 1871, VI, р. 192. 
° James Orton. The glacial deposits of the valley of the Amazons. Geol. Mag. 
1870, VIL, p. 640, 
: Н. W. Woodward. The Tertiary shells of the Amazons valley. Annals Mag- 
azine Natural History, ser. 4, Jan. and Feb., 1871, VII., p. 59-64, 101-109. 
