The "lithothamnion ridge" along the outer edge of the southeast reef of Maer Island. 

 The ridge i-- shown laid hare at the low spring tide of Septemher 30. 1913. 



Two stocks of Seriatopora histrix, which were removed from their habitat at about 1,000 

 feet from shore and taken into shallow water near the beach in order to be photo- 

 graphed. The top of the larger stock is cut off squarely at the level of lowest tides 



