278 bulletin: museum of comparative zoology. 



PLATE 18. 



The dunes south of Rio Grande do Norte, near tlie nioutli of the river. See pages 

 35 and 121. 



PLATE 19. 



The dunes nortli of the mouth of the river at Rio Grande do Norte This is a 

 characteristic bit of tlie coast north of NataL See page 122. 



PLATE 20 a. 



The northern end of the stone reef at Natal, taken from the anchorage behind the 

 reet. Part of panorama with Phite No. 20 b. See pages 35-39. 



PLATE 20 b. 



The stone reef at Rio Grande do Norte, from tlie anchorage behind the reef. The 

 fort (Fortaleza dos Reis Mages) is built upon tlie reef. This plate forms a 

 panorama with Plate 20 a. See pages 35-39. 



PLATE 21. 



The southern part of the Cunhahu stone reef, looking north from the dunes. See 

 pages 40-45. 



PLATE 22. 



Looking south over the north end of the Cunhalui stone reef toward Bahia Formosa. 

 See pages 40-45. 



PLATE 23. 



The north end of the Cunhahu stone reef at low tide where it joins the land. See 

 pages 40-45. 



PLATE 24. 



Looking northward toward Ponta da Pipa and the north end of tlie Sibauma reef. 

 See pages 40-45. 



PLATE 25. 



Boulder-like masses of sand held together by worms ; on the beach one mile north 

 of Bahia Formosa. See pages 44 and 45. 



PLATE 26 a. 



The south end of the Trai^ao sandstone reef, at low tide. (No. 26 b joins this on 

 the right to form panorama.) See pages 45-47. 



