NO. 6 ECHINOID DISTRIBUTION AND HABITS — KIER, GRANT II 



Hazvk Channel and its offshore edge. — (Stations 6, 32, 33, 46) 

 cloudy water, fine sand and silt bottom with dense turtle grass ; depth 

 10-18 feet; numerous worm burrows and mounds, small free-living 

 scleractinian corals, crabs, starfish (Linckia) ; echinoids : Lyt echinus 

 variegatus (very abundant, about 1.5-2 feet apart, small), Arbacia 

 punctulata, Diadema antillarum (rare), Clypeaster rosaceus (less 

 abundant than L. variegatus). 



Back reef channel— (Stations 10, 12, 14, 15, 24, 27, 28, 31, 51, 52) 

 sand and silt bottom, grassless patches and patches of turtle grass 

 (small reef patches discussed separately) ; depth 10-26 feet (shoaling 

 to reef patches) ; water normally cloudy, turtle grass covered with 

 "dust" ; small sponges and scleractinian corals, numerous holo- 

 thurians, worm burrows; echinoids: Eucidaris tribuloides (few), 

 Lytechinus variegatus (abundant), Tripneustes ventricosas (few), 

 Arbacia punctulata (few), Diadema antillarum (many, in groups of 

 3-5), Clypeaster rosaceus. Station 14 is clean sand with no echinoids. 



Reef patches in back reef channel. — (Stations 13, 15, 27) hard rock 

 bottom with patches of thin sand; depth 5-10 feet; many corals and 

 sponges, fish; echinoids: Echinometra lucunter (on coral), Arbacia 

 punctulata (under edge of sponge), Diadema antillarum, Clypeaster 

 rosaceus (on sand patches) . 



White Bank. — (Stations 11, 11a, 23, 24, 45, 50 and offshore ends 

 of stations 27, 51, 52) depth 10-12 feet, 3-6 feet over shoals; broad 

 areas of white, rippled sand, patches of sparse turtle grass ; echinoids : 

 Eucidaris tribuloides (few), Lytechinus variegatus (abundant, in 

 grass), Tripneustes ventricosus (few in grass), Diadema antillarum 

 (few, in grass and on rock at station 50), Leodia sexiesperforata (in 

 sand), Encope michelini (in sand), Clypeaster subdepressus (in 

 sand), C. rosaceous (in grass and on sand), Plagiobrissus grandis 

 (in sand), Meoma ventricosa (in sand). 



Interreef channel— (Stations 2, 20, 21, 22, 29, 30, 39, 44, 49, 53, 

 54, 56, 57, 58) depth 15-35 feet; broad areas of clean, white, rippled 

 sand, with large irregular, slightly elevated patches of turtle grass; 

 echinoids in sand areas : Encope michelini, Leodia sexiesperforata, 

 Clypeaster subdepressus, C. rosaceus (near edges), Meoma ventricosa 

 (large), Plagiobrissus grandis, Schisaster (Paraster) floridiensis 

 (dead), tiny Lytechinus variegatus and Tripneustes ventricosus in 

 clumps. Echinoids in turtle grass: Eucidaris tribuloides, Lytechinus 

 variegatus, Tripneustes ventricosus, Diadema antillarum, Clypeaster 

 rosaceus, Brissus unicolor (dead), Meoma ventricosa (small). 



Living coral reef. — (Stations 1, 26, 43, 60) depth 10-25 feet, high 

 relief; abundant niches in both living and dead parts of reef, in- 



