SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. I49 



tends from the shore to just beyond the outer boundary of the Reef 

 Preserve, between the Grecian Rocks and the Molasses Reef Light, an 

 area of about 55 square miles (fig. 2). 





Fig. 2. — Contour map of area studied; depth contours in feet; numbers refer 

 to stations; numbered straight lines are traverses. Map adapted from 

 U. S. Coast and Geodetic Survey chart 1249. 



Several different environments are present in this area ; each that 

 has a bearing on the distribution of the echinoids is described below 



