bkanner: the stone reefs of brazil. 255 



about the edges of the reefs also, wherever there are accumulations of 

 sediments they are in the form of calcareous mud that is blue a few 

 centimetres below the surface, but cream-colored to yellow and buff on 

 the surface. 



The chapeiroes or isolated masses are at various depths beneath the 

 water ; some of them even reach the surface at low tide. Those whose 

 summits are uncovered at low tide have very fiat tops. Their sizes and 

 forms in plan are simply endless. In some places they are so abundant 

 that they are only from one to six metres apart, and pretty evenly spaced ; 

 again they are but sparsely scattered over large areas. 



It is on these growing isolated masses that the best examples of coral 

 heads are found. I was rather disappointed, however, in the corals of 

 the Lixa reefs. Really fine examples can be had here only at the lowest 

 spring tides. The biggest heads accessible were not more than from 

 forty-five to sixty centimetres in diameter. 



The facts that most impress one in regard to the Parcel das Paredes 

 reef are (1) that the upper portion of it is completed and dead, (2) that 

 its growth is now confined to filling in the channels that separate its 

 larger portions, and (3), that the final completion of the still growing 

 portions consists in the extension of the isolated stumps until the spaces 

 between them are closed. In many places these stumps are so thick 

 that the reef ma}'^ be said to be in its last stages of growth. 



The reef is weaker in its development on the landward side than from 

 the centre eastward, and its landward side is about a metre lower than 

 the highest parts. The smoothness of the surface of these reefs as 

 compared with the reefs of the northern coast is remarkable. And 

 this smoothness is noticeable in all the reefs seen from Cabral Bay 

 southward. 



As a place for collecting corals the Parcel das Paredes is no better 

 than scores of more accessible reefs along the coast of Pernambuco and 

 Alagoas. It has the advantage of not having been so much explored by 

 lime-burners as many of the northern reefs, but it has the disadvantage 

 of being a long way from land, with inconvenient sand-bars between the 

 land and the reefs. 



An elevation of eight metres would kill nearly all of the living parts 

 of the Paredes reefs, but an elevation of two metres would not aftect 

 them seriously. 



I was told by a pilot who has lived at the Bai'ra do Caravellas for forty 

 years, that the currents inside of the Abrolhos and Parcel das Paredes 

 reefs set strongest to the southwest in May, June, and July, that they 



