BRANNER: THE STONE REEFS OF BRAZIL. 93 
The outer reef is the largest, or rather the longest and most compact 
of the three at this place. It is the Pratagy reef, properly speaking, and 
lies across the mouth of the river, which flows north 
both ends of it. It has a width varying 
metres. 
The rocks of these reefs are 
brown color. 
One hundred and Seventy metres south of the P 
one of similar materials upon the beach. 
dred metres long and seems to be a part of the southward continuation 
of the inner or beach reef exposed just north of the mouth of the river. 
The rock of this particular beach reef has a decided seaward dip, but 
in addition the top of the reef is worn off so that the upper surface 
itself has a seaward slope, 
and south round 
between eight and twenty 
quite hard and compact, and of a light- 
ratagy reef is another 
This one is about four hun- 
Fra. 60. Section of the Rio Pratagy sandstone reef. 
This characteristic has been observed in several other of the rock reefs 
of the coast. 
It is noticeable that these Pratagy reefs are not straight. 
Outside of the outer stone reef are two other parallel 
These reefs were not examined, but from 
judge them to be coral reefs. The most d 
to be about one kilometre out from the be 
to it. 
The stone reefs of Bahia. — 1 have visited the stone reefs of Bahia 
Several times, especially those at and near the lighthouse at the en- 
trance to the bay, but I have not examined their full extent along the 
Coast to the east of the lighthouse. As is well shown in the accom- 
panying illustration of these reefrocks, the blocks about the lighthouse 
have the appearance of having been undermined and broken into great 
angular slabs. 
The Bahia reef is not exposed in a long beach-like line, as are most of 
the other sandstone reefs, Here there has been no stream enterir 
ocean from behind a bar, but the horizontal в 
Sets of reefs. 
their general appearance Т 
istant one of these appears 
ach and approximately parallel 
18 the 
and rock has been exposed 
by the encroachment of tho. sea Upon accompanying beds. The reef 
appears to rest upon the edges of crystalline rocks. 
