Sea (Continued) 

 areas of occurrence of biomes of, 



351 

 as source of food for man: 

 and chief marine organisms used, 



371 

 and difficulties of use of plankton, 



371 

 and oyster production, 371 

 apparent inexhaustibility of, 371 

 through fin fish, 371 

 average depth of, 351-352 

 balanoid- gastropod- thallophyte 



biome of: 

 algae as protecting animals in 



littoral zone of, 363 

 anchoring devices of organisms 



in, 362 

 and characteristic animals in 



sublittoral zone of, 363 

 avoidance of dessication by 



organisms of, 362 

 benthos of as mostly epifauna, 



362 

 density of species in sublittoral 



zone of, 363 

 dominance in, 364 

 elements in food chains of, 364 

 extension of sublittoral zone in, 



362 

 extensions of, 362 

 infralittoral fringe of, 362 

 kelp in sublittoral zone of, 363 

 midlittoral or balanoid zone of, 



362 

 movement of animals into proper 



zones of, 362-363 

 protective devices of animals of, 



364 

 species of animals in littoral 



zone of, 363 

 sublittoral zone of compared to 



littoral zone, 363 

 succession in, 364 

 supralittoral fringe of, 362 

 supralittoral zone of, 362 

 tidal pools in, 364 

 composition of benthos in, 359 

 coral reef biome of: 

 as found only in tropics, 370 

 atoll reefs in, 366-367 

 barrier reefs in, 366-367 

 biomass in, 367 



calcareous as cement for struc- 

 tures of, 366 

 colors of corals at water's 



surface in, 366 

 dominants in, 367 

 formation of, 366 

 fringing reefs in, 366-367 

 intolerance of organisms of to 



freshwater, 366-367 



Sea (Continued) 



lack of predation pressure and 



color of fishes in, 367 

 predominant organisms of, 366 

 repair of damage in, 366 

 secondary species in, 367 

 symbiosis in, 366 

 depth of trenches of, 351-352 

 difficulties in recognizing com- 

 munity units in, 351 

 distribution of benthos in, 359 

 drop in temperature of in tropics 



during Pleistocene era, 284 

 extension of littoral zone of, 351- 



352 

 extension of sublittoral zone of, 



351-352 

 increase in pressure at great 



depths of, 353 

 internal pressures in animals as 

 balancing external pressures 

 of, 353 

 level of in post- Pleistocene era, 



288 

 level of during Pleistocene era, 



284 

 light in: 

 and photosynthetic zone, 287 

 as varying with depth, 283 

 compensation point of, 284 

 nekton of: 

 birds of as more numerous in 

 neritic biochore than in open 

 ocean, 291 

 composition of, 291 

 distribution of fish in, 291 

 species of birds in, 291 

 oceanic biochore of, 280-281 

 oceanic plankton and nekton biome 

 of: 

 and daily productivity of plankton 



in Block Island Sound, 361 

 and Sargassum Community of 



Atlantic Ocean, 359 

 as characterized by organisms 

 with life-forms adapted for 

 floating, 359 

 as complete ecosystem, o59 

 aspection and changes in species 



composition of, 359 

 bathy- and abyssopelogic com- 

 munities of, 359 

 bioluminescence of deep-sea 



forms in, 360 

 depths of nitrogen regeneration 



in, 360 

 derivation of forms in greater 

 depths of from intermediate 

 depth forms, 360 

 epipelagic community of, 359 

 factors in variations in produc- 

 tivity of plankton of, 361-362 



Sea (Continued) 



filter- feeding mechanisi 



organisms in, 361 

 fish m food chains of, 360-361 

 food of net zooplankton in, 361 

 invertebrates in food chains of, 



360-361 

 mesopelagic community of, 359 

 productivity of phytoplankton, 

 zooplankton and fish of, com- 

 pared, 361 

 role of bacteria in food chains 



of, 360 

 secondary communities in due to 

 variation of species composition 

 of with depth, 359 

 sharks in food chains of, 361 

 undissolved organic matter in 



food chains of, 360-361 

 uniformity of habitats in as per- 

 mitting ancient forms to per- 

 sist to present, 360 

 upwelling water currents and 



food chains of, 361 

 special structures of animals to 

 permit vision at great depths 

 of, 360 

 whales in food chains of, 361 

 oxygen in: 

 adaptations of marine animals 



for obtaining, 356 

 factors in concentrations of, 356 

 sources of, 356 

 pelecypod-annelid biome of (see 

 also Sea, Coral Reef Biome of): 

 animal burrows in, 364 

 areas of occurrence of, 364 

 burrowing as characteristic of 



animals of, 365 

 characteristics of crustaceans 



in, 365 

 deposit-feeders in, 365-366 

 dominance in, 366 

 epifauna in, 365 



feeding habits of fish in, 365-366 

 high tide in and feeding activities, 



366 

 low tide in and feeding activities, 36( 

 microscopic forms in, 365 

 mud content of shores in, 364 

 nature of water action in, 364 

 predominant animals in, 365 

 principal food chain in, 365-366 

 productivity of, 366 

 recognition of secondary com- 

 munities in, 365 

 respiration of burrowing animals 



in, 365 

 role of bacteria in food coactions 



of, 365 

 species of plants in, 365 

 suspension- feeders in, 365-366 



440 Index 



