220 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
fined to the immediate neighborhood of the shore, coral reefs frequently 
lie some distance out, at times forty or fifty miles.” 
Rathbun, Richard. Notes on the coral reefs of the island of Itaparica, 
Bahia, and of Parahyba do Norte. Proc. Boston Soc. Nat. Hist., 
1878, XX., p. 39-41. 
Notes on the characters of the coral reefs at the places mentioned. 
Rathbun, Richard. Prof. Hartt on the Brazilian sandstone reefs. 
American Naturalist, June, 1879, XIIL, р. 347-358. The author 
states that the paper “is partly in the very words of Prof. Hartt,” 
but it ig not always clear which parts Hartt is responsible for, or 
which are to be credited to Mr. Rathbun. 
In any case this article is the most important one ever published upon 
the stone reefs of Brazil. It includes Hartt’s own work done previously, 
and also most of the results of the work by the Commissio Geologica do 
Brazil on the reefs at Pernambuco, Porto Santo, Bahia, and Porto 
Seguro. In regard to the height of the reef at Pernambuco it is stated 
that it is about the same as high tide, “though on account of the great 
commotion made by the waves at such times, it is impossible to exactly 
determine this fact. . . . It is very evident that they [the reef rocks] are 
not the outcropping edges of beds of sandstone . . . but only narrow 
strips of stone of slight thickness formed in exactly the same position in 
which we see them to-day, that is, just below the level of high tide.” 
This solidification is considered to be due to lime carried into the beach 
materials by percolating waters, both sea-water and rain, and by the 
“encroachment of the sea aided by rivers flowing behind them these 
consolidated beaches have often been separated from the main shore as 
distinct reefs ; but sometimes this latter action has not taken place, and 
the hardened layer retains its normal position upon the beach.” The 
dip of the beds is attributed to the false bedding of the beach sand as 
deposited and not to the upheaval of the coast. Of the Porto Santo 
reef on Itaparica at Bahia it is said that there must have been an eleva- 
tion to raise the reef at that place so high above water. 
Rathbun, Richard. A praia consolidada e sublivada e 08 sambaquis de 
Porto Santo. Archivos do Museu Nacional do Rio de Janeiro. 
1878, ПІ., р. 172-174. 
Mr. Rathbun describes a stone reef at Porto Santo on the northeast 
corner of the island of Itaparica, which lies within the Bay of Bahia and 
northwest from that city. 
