P

1. Pacific Ocean (see also North Pacific and South Pacific):

   1. boundaries, 11

   2. equatorial region, 706–712

      1. currents, 708–712

      2. oxygen content, 710, 711

      3. phosphate, 710, 711

      4. silicate, 710, 711

      5. water masses, 706–708

   3. oxygen distribution, 728–730, 753

2. Palagonite, 1027

   1. frequency of occurrence, 987

3. Pelagic environment and its subdivisions 278

4. Pelagic sediments (deposits), 972

   1. areas covered by, 977

   2. average percentage of calcium carbonate, 1006

   3. chemical composition, 991, 992

   4. classification, 972–973

   5. color, 978, 979

   6. content of organic matter, 1015

   7. depth range, 978

   8. distribution, 974–978

   9. inorganic constituents, 986–990

   10. iron content, 992, 1030–1032

   11. manganese content, 992, 1028–1031

   12. minerals, 986–990

   13. organic constituents, 983–986

   14. phosphorus content, 992, 1032

   15. radium content, 1034, 1035

   16. rate of deposition, 1038, 1039

   17. texture, 979–982

5. Pendulum day, 437

6. Permeability of sediments, 994

7. Persian Gulf, 690

8. Peru Current, 701–705

   1. comparison with California Current, 703

   2. organic production in, 942

9. Petroleum formation in marine sediments, 947, 1009

   1. possible role of bacteria, 996

10. Pettersson-Nansen water bottle, 352

11. Phaeocystis, 301

12. Phillipsite, 1027

    1. frequency of occurrence, 987

13. pH of sea water, 193

    1. determination, 193, 194

    2. distribution, 208–210

    3. role in carbon dioxide system, 195–202

14. Phosphate:

    1. as a limiting factor, 768, 788

    2. distribution:

       1. factors influencing, 246, 247

       2. in basins, 245, 246

       3. in oceans, 239–241

          1. related to deep-water circulation, 754

       4. in South Atlantic, 786–788

    3. regeneration, 260–261

       1. in isolated areas, 932

    4. seasonal variation, 258

    5. utilization of, by plants, 768, 931–932

15. Phosphate-phosphorus, ratio to nitrate-nitrogen, 236, 243

16. Phosphorescence (see Bioluminescence)

17. Phosphorite nodules, 952, 1032, 1033

18. Phosphorus, 182

    1. in red clay, 1030, 1032, 1033

    2. organic, in sea water, 257

19. Phosphorus cycle in the sea, 260–261, 916

20. Phosphorus-nitrogen ratio in plankton, 236

21. Photosynthesis of phytoplankton, 774

    1. energy and illumination, 776

    2. experiments, 777–782, 933

       1. assimilation, 777

22. Photosynthesis ratio to respiration, 933

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― 1072 ―

23. Physalia:

    1. reproduction, 320

    2. systematic position, 306

24. Phytoplankton (see also Plankton):

    1. collection and analysis, 382–383

    2. number of important species in, 762

    3. photosynthesis, 774–782

    4. relation to zooplankton, 898–904

25. Phytoplankton production, 923–934

    1. factors of (see Diatoms and Dino-flagellates)

    2. index of:

       1. direct census, 927

       2. oxygen production and consumption, 933–934

       3. plant nutrient consumption, 931–933

       4. plant pigment units, 928

26. Pigments extracted from mud, 969

27. Plankton (see also Phytoplankton and Zooplankton), 281

    1. adaptations, 821–823

    2. collecting methods, 376–383

    3. equivalents, 929

    4. macro-, micro-, and nannoplankton, 819

    5. neritic, 820

    6. oceanic, 821

28. Plankton and filter feeders, 886–892

29. Plant nutrients, 235

    1. and vertical circulation of water, 782–790

       1. convection, 790

       2. regions of divergence and convergence, 787, 788

       3. stabilization, 789

       4. turbulence, 787–789

       5. upwelling, 785–786

    2. factors influencing distribution, 235, 236

    3. renewal in surface layers:

       1. Antarctic region, 620

       2. Equatorial Countercurrent, Atlantic, 636

       3. Equatorial Countercurrent, Pacific, 712

       4. North Atlantic, 682

       5. off coast of California, 725

       6. off coast of Peru, 702

       7. off west coast of South Africa, 628

    4. storage in the sea, 784–785

    5. winter maxima and summer minima, 939

30. Plants (see also Algae and Eel grass):

    1. higher plants, 302–303

    2. major producers in the sea, 287

    3. Thallophyta, 288–302

31. Platyhelminthes, 307

32. Pleurobrachia, 307, 890

33. Polymerization of water, 47

34. Population, 162

35. Porosity of sediments, 993, 994

36. Portuguese man-of-war (see Physalia)

37. Potassium, 179

38. Potential temperature (see Temperature)

39. Pressure (see also Isobaric surfaces):

    1. as an ecological factor, 273

    2. field of, 405

    3. internal field, 408

    4. total field, 413

    5. units, 55, 170

40. Pressure gradient, 405

41. Preying animals, 896–898

42. Primary food of the sea, 882, 883

43. Production (see Organic production and Phytoplankton production), 162

    1. importance of, to organic matter in sediments, 1011, 1015

44. Projections, map, 10

45. Protozoa:

    1. reproduction, 319

    2. synopsis, 304–305

46. Pteropod ooze (see Pelagic sediments)