226 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
IX. 
The Coral Reefs. 
PAGE Paan 
LOM Germs ss e r + 220 Between Itaparica and Cara- 
The Rocas . . | € у M0 : vellas . po T SN 
Cape St. Roque reefs SA 0 ОД Caravelas- o 1 v 961 
Lavandeirareefs . . . . . 228 Abrolhos reefs . . 256 
doao да Cunha s : i ги 228 Thickness of the coral reefs of 
Ceará reefs . . Lcd. ui 208, Brasil vcs i «+ 50 
Fernando de Noronha © зк 200 The age of the coral reef 01 
Parahyba do Norte . . 282 Chemical composition of Bra- 
Between Parahyba and Recife 235 plian corali cus 200 
Pernambuco to Santo Aleixo . 236 List of corals of the coast of 
Santo Aleixo. . . kc OL BRAZIL 702 ta 399 
Between Santo Aleixo and Notes on corals collected. By 
MATO ио ис 200 A. Wi Greeley 4: . 1 268 
Analysis of reef rock p 24] The Maceio coral reef . . . 270 
The Bahia тео, v ооо 7 240 Conclusions regarding the coral 
ГЕ so x or FIA 
When the work on the stone reefs was begun it was not intended to 
include with it anything upon the coral reefs. It was only after the 
work was nearing completion that it seemed advisable to utilize the notes 
made on the corals, and to use the geological history of the stone reefs 
as far as possible to throw light upon that of the coral reefs. For this 
reason these notes are fragmentary. I have endeavored, however, to 
bring together what others have written upon the coral reefs in order to 
make the paper as nearly a complete account of the coral reefs of Brazil 
as can be written with our present information. 
The accompanying map shows the distribution of the coral reefs so far 
as it is known (Plate 1) at present. 
LocaL DETAILS. 
The Rocas. — In 1852 the Rocas was visited and was first mapped 
and described as a coral island." This island is eighty-four miles due 
west of the Peak of Fernando de Noronha, and one hundred and forty- 
four miles from the Brazilian mainland. Its centre is in south latitude 
1 Report and charts of the cruise of the U. S. Brig “Dolphin” made under the 
direction of the Navy Department, by Lieutenant S. P. Lee. U.S. Navy, Wash- 
ington, 1854 (33d Cong., Ех. doc. 59, р. 81-85). 
