230 ORVILLE A. DERBY 
certain that a horizontal position, even when general, is a sure index 
of Tertiary age, although this hypothesis has, for this region, a strong 
presumption in its favor. Thus far the only known fossils in the 
beds referred to this age are the leaves of Ouricanguinhas from the 
high tableland (400 meters) back of Alagoinhas, which has been 
referred to the Pliocene (17, 18). As all the species are described 
as new, it is possible that they may prove to be somewhat older. 
Between this horizon and that of the fossiliferous beds discussed 
above there is almost certainly one (and there may be several) geo- 
logical divisions to be established; but where the dividing line, or 
lines, between them—that is to say, between some horizon, probably 
not the extreme upper one, of the Cretaceous and a horizon of the 
upper Tertiary—is to be drawn must remain a subject for future 
study. Branner’s protest against drawing it at the top of the known 
fossiliferous beds is a timely one, and his reserve in the matter of 
indicating another position for it is significative of the difficulties of 
the subject. 
From Bahia southward for a considerable distance along the 
coast sedimentary beds similar to those about the bay have been 
reported from a number of points, so that it is tolerably certain that 
the formation is, or was formerly, continuous from Bahia to the region 
of Maraht which has recently been examined by Gonzaga de Campos 
(15), and more cursorily by myself. The former reports, in addi- 
tion to the marine beds already mentioned, a sandstone with carbon- 
ized wood which he compares very properly with the similar strata 
about Bahia. ‘The relative position of the marine and fresh-water 
beds could not be positively determined, but he was inclined to think 
that the former overlie the latter. Without being positive on the sub- 
ject, it seems to me that the contrary will prove to be the case. ‘These 
beds scarcely rise above tide-level and can be well seen only at extreme 
low tide, so that a proper examination of their numerous widely 
separated localities involves many days’ labor. The soft parti- 
colored sandstone most in evidence in the region is apparently with- 
out fossils and apparently horizontal, and for these reasons Campos 
referred it to the Tertiary, and assumed that the “turfa’’? deposits 
t The so-called turfa of Maraht is, in part, a peculiar light (sp. gr. 0.92), non- 
schistose, bituminous substance of earthy aspect and yellow color, containing about 70 
