76 C, B. BROWN ON THE TERTIARY DEPOSITS ON THE 
6. On the Tertiary Deposits on the Sorimons and Javary Rivers, in 
Brazit. By C. Barrrneton Brown, Esq., F.G.S., Assoc. R.S.M. 
With an AppENnDIx, by R. Eruuripver, Esq., F.R.S., V.P.G.S. 
(Read June 19, 1878.) 
[Puate VII. | 
Wartst engaged on the Geological Commission of the Amazon Steam 
Navigation Company of London, in the year 1874, I had an oppor- 
tunity of examining some beds on the banks of the Solimées, or 
Upper Amazon, and one of its tributaries, the Javary, which con- 
tained similar species of fresh- and brackish-water shells to those 
found in the Tertiary beds at Pebas, still further up the Amazon. 
These, I naturally concluded, were part of a southerly extension of 
the same deposit; and my conclusion is, I think, borne out by the 
facts. 
Thinking that any additional records of this highly interesting 
Tertiary deposit might prove acceptable to geologists, | have em- 
bodied the scanty results of my inyestigations in the present paper. 
Amongst the fossils I collected were some hitherto undescribed 
genera and species, which have now been examined by Mr. Etheridge, 
who has described them in an Appendix which he has done me the 
honour to attach to this paper. 
The late Professor Orton was the first to mention the occurrence 
of fossiliferous beds on the Amazon; and Mr. Gabb, to whom he 
submitted the fossils for examination, pronounced them to be of 
Tertiary age. As Professor Hartt, in a paper ‘‘On the Tertiary Basin 
of the Maranon,” published in the ‘American Journal of Science 
and Arts,’ vol. iv. July 1872, has already pointed out, Professor 
Orton erred in stating that these shells occurred in “ the coloured 
plastic clays which stretch unbroken from the foot of the Andes to 
the Atlantic ;’? while Mr. Woodward, in his paper* on the Pebas 
fossils collected by Mr. Hauxwell, arrives at the mistaken conclusion 
that the Pebas beds are “‘evidently bed II. of the late Professor 
Agassiz’s ideal” and erroneous “ section.” i 
Professor Hartt having very thoroughly examined the Ereré 
district, across which Professor Agassiz’s section was run, is better 
able than I am to speak upon the subject; and I therefore refer 
any one interested in the matter to the first paragraph of page 58 of 
his paper above mentioned. 
tegarding the error first referred to above, it 1s easy to see that 
Professor Orton has confounded together two distinct deposits—one 
being an old river-formation composed of coloured clays beneath, 
and white, red, and yellow sands above, capped by red clayey loam 
which passes into the sands; and the other, part of a set of blue 
fossiliferous clays containing seams of impure lignite. 
This old river-deposit, spreading over a great portion of the 
* «Annals and Magazine of Natural History’ for January and February 1871. 
