DARV/IN BAY is partly fringed by rocky escarpments as shown 

 in this view taken on the 1927 voyage of the Oaxaca. Volcanic 

 vents fringing the near side of the bay still gave forth sulphur- 

 ous fumes in 1938. In making their nests the booby birds, as 

 shown below, clear a small space of sticks and stones. In the 

 tropical heat they sometimes stand over their eggs, shading 

 them to keep them cool, instead of hovering to keep them warm. 



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