BRANNER: THE STONE REEFS OF BRAZIL. 79 
tinues that far, must carry them beneath the coral reef that lies a few 
hundred metres off shore at this place. 
The Cacimba and Serinhaem stone reefs. — The Rio Serinhaem enters 
‚ the ocean in south latitude 8° 36/, just east of the island of Santo 
Aleixo. The Cacimba and Serinhaem reefs lie across 
the mouth of this river and in front of the flat lands 
immediately north of it. 
The Cacimba reef is largely on the beach at the bot- 
tom of the embayment between Ponta do Serramby and 
Rio Serinhaem, while the Serinhaem reef lies across the 
mouth of the river and extends well to the north, afford- 
ing partial protection to the embayment west of it. 
The country west of these reefs consists of a narrow 
strip of sandy land next to the beach, with mangrove 
Swamps and sandy flat lands behind. These low flat 
lands about the mouths of Rios Serinhaem and Trapiche 
extend back to the foot of the Tertiary hills that rise 
a few kilometres inland. 
At the town of Barra de Serinhaem, soft black Ter- 
tiary sandstones are exposed at low tide along the river 
bank for a distance of several hundred metres. 
The northern end of the Cacimba reef begins on the 
beach south of Ponta do Serramby at a place called 
Cacimba. A sand bank three metres high rises on the 
land side of it, and two hundred metres west of the beach 
а mangrove swamp follows southward parallel with tho 
shore. 
Fic. 49. Section across Ше Cacimba stone reef. 
The northernmost four hundred metres of this reef 
lies upon the beach; then follows a break, beyond which 
it touches the beach at only one point. It is a striking 
and interesting fact that the southern end of this reef 
curves gently eastward with the beach 
parallel with 
from it. 
The south end of the Cacimb 
, Keeping al Ways 
it and from forty to sixty metres away 
а reef is more or less broken, until at last 
16 appears only as isolated patches, and finally drops in behind or land- 
ward of the Serinhaem reef, and comes to an end. 
About its northern end this reef в 
at low tide ; near its south end it is 
much cracked, broken, a 
tands fully two metres out of water 
not quite so high. The surface is 
nd etched lengthwise, and there is a great 
