reef. Over the surface are 

 the customary tide-pools, 

 though but few of them 

 have any considerable depth. 

 These pools lie mostly along 

 lines parallel with the main 

 axis of the reef. Much of 

 the surface is covered with 

 light green seaweeds. 



The rock of the reef is a 

 hard sandstone of a light 

 brown color and contains 

 many fossil shells. 



The Traifao reef, perhaps, 

 more than any other one ex- 

 amined shows the effects of 

 the wear and tear of the 

 surf. Inside the reef there 

 are many blocks buried iu 

 the sands, apparently broken 

 from the outer face and 

 thrown across by the waves ; 

 the outer edge is decidedly 

 serrate, seldom presenting a 

 bold face to the sea. Here 

 and there the waves have 

 opened beneath the reef great 

 caverns in which they can be 

 heard to swash back and 

 forth. Sometimes these 

 waves can be felt to jar the 

 whole reef surface over an 

 area of several hundred 

 square metres. 



For details of other charac- 

 teristics of this reef reference 

 is made to the description of 

 that of the Mamanguape. 



The Mamanguape stone 

 reef. — The Mamanguape 

 reef is one of the largest and 

 most impressive of the stone 

 reefs of Brazil. It is here 

 described as a separate reef, 

 but properly speaking it is 

 continuous with the Traii^ao 

 reef to the north of it, and 



STONE 



ESTA?0 



DRAZIL 



nABonTnAvx-Ms 



C CCILM.\N 



Fig. 19. 



