170 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
The coast lakes formed by the closing of the mouths of estuaries 
such as Lago’ Manguaba, Lagoa do Norte, Jiquiá, Sinimbü, eto. 
d, Embayments altogether filled up. 
e. The islands along the coast are nearly all close in-shore and have 
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the appearance of having been formed by depression of the land. 
f. The buried rock channels at Parahyba, now filled with mangrove 
swamps and mud, show a depression of at least twelve metres 
since those channels were cut. 
g. Wind-bedded sand below tide-level on Fernando de Noronha. 
10. The evidences of elevation consist of : — 
а. Elevated sea beaches especially well shown about the Bay of 
Bahia, and along the coast of the State of Bahia. 
b. Marine terraces about Ilheos in the State of Bahia. These are 
about eight metres above tide level. 
c. Horizontal lines of disintegration about one metre above high 
tide in granites and gneisses at and about Victoria, State of 
Espirito Santo. 
d. Burrows of sea-urchins so far above low tide that sea-urchins can 
not now live in them. These are well shown at Pedras Pretas 
on the coast of Pernambuco. 
11. Of the two movements the depression has been much the greater 
and was the earlier. 
12. The great depression probably took place in early Pliocene times. 
(See the chapter on Geology, pages 8 to 33.) 
13. Following the Pliocene depression of the coast, the headlands were 
strongly eroded, the mouths of bays and estuaries were closed, and the 
coast line straightened. 
14. The sandstone reefs of the coast were formed and hardened sub- 
sequent to the depression. 
15. The coral reefs of the coast have helped build out the shores, and 
they have likewise protected the land from the destructive action of the 
waves. 
16. The stone reefs have also protected the land, and have helped to 
prevent the encroachment of the sea. 
17. The mangrove swamps have been important agents in building up 
the newly formed land about estuaries and embayments. 
18. The sands of the coast are not of foreign origin, as has been sur- 
mised, but are derived from the adjoining headlands, or they have been 
brought down from the land by streams. 
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