220 bulletin: museum of comparative zoology. 



fined to the immediate neighborhood of the shoi-e, 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 JS^orte. 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, XIII., p. 347-358. The author 

 states that the paper " is partly in the very words of Prof. Hartt," 

 but it is not always clear which parts Hartt is responsible for, or 

 which are to be credited to Mr. Eathbun. 

 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 Commissao 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 os sambaquis de 

 Porto Santo. Archivos do Museu Nacional do Rio de Janeiro. 

 1878, III., p. 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 ciu't city. 



