100 bulletin: museum of comparative zoology. 



thus far examined. These, however, are not the only stone reefs of the 

 noiitheast coast of Brazil. There still remain several that have not been 

 examined and about which very little is known. Under the circum- 

 stances it seems best to give that little here, and to mention the places 

 at which stone reefs are reported, whether anything else than their 

 existence is known about them. 



Some important reefs may have beeu omitted from this list, but it is 

 doubtful Avhether facts to change any of the conclusions reached would 

 have been obtained by an examination of the reefs not seen. 



In mentioning "reported" reefs, proper allowance has been made, in 

 so far as possible, for the general disposition to lump all the reefs of this 

 coast together. To navigators all reefs are pretty much alike, so much 

 so that the Pernambuco stone reef, the best-known one of Brazil, is often 

 put down in sailing directions for the south Atlantic as a coral reef. The 

 confusion is further increased by the customary addition that this same 

 reef borders the whole Brazilian coast. With such reports as these we 

 tiy to have nothing to do. 



On my trip from Pernambuco to Natal in June, 1899, for the purpose 

 of studying the reefs, it was not possible to examine all the places that 

 it was desirable to examine because of the inaccessibility of the shores 

 for the barcaga in which the trip was made. This difficulty was evaded 

 in some instances by following the beaches on foot, but this was not 

 always convenient, and necessarily delayed the work. 



Guaju. — There is a line of reefs beginning three or four kilometres 

 south of Pavuna (S. lat. 6° 32'), in the State of Parahyba, and stretch- 

 ing across the low lands in front of Rio Guaju. Rio Guaju enters the 

 sea thi'ongh a flat valley between rather steep-faced hills. This reef was 

 not examined, but its conliguration and the nature of the country back 

 of it lead me to believe it to be a sandstone reef. 



Sargi. — Across the month of another small stream north of the 

 Guajii, probably the Sargi, is a reef which, seen from the ocean, has 

 every appearance of being of sandstone. 



Joao dos Santos. — At Joao dos Santos a stream enters the ocean and 

 reefs lie across the mouth of it and extend two or three kilometres to the 

 south. The geography and general appearance lead me to believe it to 

 be of sandstone. 



Tihdu. — At Tibau (S. lat. 6° 11') a small stream enters the ocean 

 from behind a short reef that appears to be of recent sandstone. 



Camoi-upim. — About 2.5 kilometres north of Tibau begins a stone 

 reef which continues northward for several kilometres very close to and 



