BRANNER: THE STONE REEFS OF BRAZIL. 213 



the reef . . . its general direction oscillates a little about that of the 

 reef." He refers to the eroded condition of the reef, and to the polyps 

 on its outside face, and says the quartz grains and shells are held 

 together by a siliceous lime cement. 



The most remarkable point in this letter is that the author finds in 

 the direction of the reef confirmation of Elie de Beatimont's theory of 

 the parallelism of structural features of the earth's crust ; that the reef 

 follows these lines even more closely than the coast-line, and that it 

 agrees "with the direction of the Western Alps." 



Liais, Emmanuel, Climats, geologie, faune et geographie botanique du 

 Bresil. Paris, 1872, pp. 256-261. 

 The reefs are considered as proof of very recent elevations along the 

 Pernambuco coast (p. 256). " The reef rock is a sandstone composed 

 of quartzose grains and of fragments of shells hardened by a siliceous 

 calcareous cement, and presenting a schistoid structure." Some of the 

 shell fragments he found petrified. The beds of rock dip seaward, he 

 says, at an angle of 35° to 40°. Near Serrambi, and south of there, 

 he says, he saw on the shore a part of the reef standing vertically. He 

 states that the reef is never crooked Q' Jamais il ne se courbe^'). The 

 surface decay is noted, and the protection given by polyps. He repeats 

 his earlier statement that the coast-line is " modelled on that of the 

 reef." In age he thinks that the reef marks the close of the Quaternary 

 and shows the last elevation of the coast. 



Lisbda, Alfredo. Memoria descriptiva e justificativa do projecto do 

 meliioramento do porto do Kecife . . . por Alfredo Lisboa . . . 

 em 1887. Pernambuco, 1887. 

 This report has a very good map of the northern end of the reef. 

 The description of the Pernambuco reef is short but excellent. He ob- 

 serves that the reefs of the coast are not continuous ; that they are 

 never higher than the highest tides; he gives the direction as S. 19° 

 32' W. (true), with a length of three thousand one hundred and twenty 

 metres to the Barreta das Jangadas, and a width of twenty to sixty 

 metres. He notes the composition correctly, and thinks the sands hard- 

 ened by lime derived from the shells (p. G-8). On p. 98-100, the 

 author quotes the opinion of Hartt in regard to the origin and nature of 

 the reefs of Brazil. 



Malte-Brun, M. Universal geography, or a description of all parts of 

 tlie world. III., p. 389 and 401. Philadelphia, 1827. 



