R

1. Radiation:

   1. absorption in pure water, 80, 81

      1. illustrated, 105, 106

   2. absorption in sea water (see Radiation, extinction coefficients)

   3. effective back, 111–113

   4. extinction coefficients, 82, 84, 85

      1. cause, 87, 88

      2. influence of sun's altitude on, 86, 87

      3. of total energy, 106, 107

   5. from sun and sky, 101–104

   6. heating due to absorption of, 108–110

   7. long-wave, 98

   8. measurements of extinction, 82, 83

   9. nocturnal (see Radiation, effective back)

   10. reflection from ice and snow, 113

   11. reflection from sea surface, 104

   12. scattering, 87

   13. short-wave, 98

   14. solar constant, 102

   15. “surface loss,” 106

2. Radioacoustic ranging, 341

3. Radioactive elements, 184

   1. in sediments, 1033–1035

4. Radiolaria:

   1. reproduction, 319

   2. systematic position, 305

5. Radiolarian ooze (see Pelagic sediments):

   1. areas covered by, 977

   2. color, 979

   3. depth range, 978

   4. distribution, 975, 976

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   ― 1073 ―

   5. inorganic constituents, 984, 986–988

   6. organic constituents, 983, 986

   7. radium content, 1034

6. Radium, 184

   1. in sediments, 1033–1035

7. Red clay (see Pelagic sediments):

   1. areas covered by, 977

   2. chemical composition, 991, 992

   3. color, 979

   4. content of organic matter, 1015

   5. depth range, 978

   6. distribution, 975, 976

   7. inorganic constituents, 984, 986–988

   8. iron content, 1030–1032

   9. manganese content, 1029, 1030

   10. organic constituents, 983, 984

   11. phosphorus content, 1030, 1032, 1033

   12. radium content, 1034

   13. rate of sedimentation, 1039

   14. texture, 980–982

8. Red Sea:

   1. currents, 687–690

   2. oxygen content, 688

   3. water masses, 687, 688

9. Red Sea water, spreading of, 693, 695, 745

10. Reducing capacity, 212

    1. in sediments, 996

11. Red water, 89

12. Refractive index, 70, 71

13. Relative relief, 19

14. Reproduction (see also Life cycles):

    1. related to temperature, 846–849

    2. types, 315

15. Reproductive distribution, 315

16. Resting spores in diatoms, 299

17. Rip currents, 537

    1. importance to beach sediments, 1017, 1018

18. River water, composition of, 214–216

19. Rotifera, synopsis of, 307

20. Roughness length, 479

    1. of sea bottom, 480

    2. of sea surface, 491

21. Rubidium, 182