1. Volumen XXV

   Legacy Pages: ii - ii

2. A note on the calculation of ultimate oxygen demand

   • G. Lenhard

   OriginalPaper Pages: 1 - 7

3. Effect of current speed on the cephalic fans of the larva of Simulium ornatum var. nitidifrons Edwards (Diptera: Simuliidae)

   • Jennifer J. Harrod

   OriginalPaper Pages: 8 - 12

4. Zur Kenntnis der Testaceenfauna der slowakischen Reisfelder

   • Milan Ertl

   OriginalPaper Pages: 13 - 20

5. Thermal algae of Western India

   • Joseph Thomas
   • Ella A. Gonzalves

   OriginalPaper Pages: 21 - 28

6. Thermal algae of Western India

   • Joseph Thomas
   • Ella A. Gonzalves

   OriginalPaper Pages: 29 - 40

7. Thermal algae of Western India

   • Joseph Thomas
   • Ella A. Gonzalves

   OriginalPaper Pages: 41 - 54

8. Thermal algae of Western India

   • Joseph Thomas
   • Ella A. Gonzalves

   OriginalPaper Pages: 55 - 65

9. Thermal algae of Western India

   • Joseph Thomas
   • Ella A. Gonzalves

   OriginalPaper Pages: 66 - 71

10. Les différentes catégories de plancton

    • B. H. Dussart

    OriginalPaper Pages: 72 - 74

11. Beitrag zur Kenntnis der Art Cyclops tatricus Kozminski (Crustacea, Copepoda) in der Tschechoslowakei

    • František Kubíček

    OriginalPaper Pages: 75 - 84

12. Studies on the biology of genus Synodontis at Khartoum

    • H. M. Bishai
    • Y. B. Abu Gideiri

    OriginalPaper Pages: 85 - 97

13. Studies on the biology of genus Synodontis at Khartoum

    OriginalPaper Pages: 98 - 113

14. Two techniques for sampling freshwater habitats

    • P. A. Garnett
    • R. H. Hunt

    OriginalPaper Pages: 114 - 120

15. Symposium on new methods of determining biogenic and organic substances in water and organisms

    • H. L. Golterman
    • H. R. Krause
    • D. F. Westlake

    OriginalPaper Pages: 121 - 130

16. Oxygen consumption of profundal lake animals at low oxygen content of the water

    • Kaj Berg
    • Pétur M. Jónasson

    OriginalPaper Pages: 131 - 143

17. Some peculiarities concerning the contraction of the gametes in Spirogyra maxima (Hass. Wittrock)

    • Fr. Symons

    OriginalPaper Pages: 144 - 150

18. Radionuclide accumulation by Anodonta piscinalis Nilsson (Lamellibranchiata) in a continuous flow system

    • Karen Garder
    • Olav Skulberg

    OriginalPaper Pages: 151 - 169

19. Euglena middelhoekii nov. sp.

    • H. Ettl

    OriginalPaper Pages: 170 - 172

20. A survey of the bottom fauna of streams in the Scottish Highlands

    • Henry J. Egglishaw
    • N. C. Morgan

    OriginalPaper Pages: 173 - 183

21. Caloglossa beccarii im Golf von Mexico

    • Erika Post

    OriginalPaper Pages: 184 - 188

22. Hydrobiological studies on the Tugela river system

    • W. D. Oliff
    • P. H. Kemp
    • J. L. King

    OriginalPaper Pages: 189 - 202

23. Experiments on competition between two Asellus species (Isopoda Crustacea)

    • H. B. N. Hynes
    • W. D. Williams

    OriginalPaper Pages: 203 - 210

24. Monographische studie der Gattung Hyalosphenia Stein

    • Th. Grospietsch

    OriginalPaper Pages: 211 - 241

25. The ecology of solar sewage drying beds in the Pirana Sewage Farm at Ahmedabad

    • S. V. Ganapati
    • I. P. S. Prasadarao
    • Thomas Koshy

    OriginalPaper Pages: 242 - 270

26. Studies on bottom deposits of the Vaal River system

    • G. Lenhard
    • A. du Plooy

    OriginalPaper Pages: 271 - 291

27. Les formes zoogènes de tufs et leur formation dans la région des Lacs de Plitvice en Yougoslavie

    • Ivo Matoničkin
    • Ziatko Pavletiíc

    OriginalPaper Pages: 292 - 300

28. Bostrychia scorpioides im tropischen Westafrika

    • Erika Post

    OriginalPaper Pages: 301 - 306

29. A laboratory study of predation on lake-dwelling triclads

    • J. O. Young
    • T. B. Reynoldson

    OriginalPaper Pages: 307 - 313

30. In memoriam Hubert Damas

    • P. Van Oye

    Announcement Pages: 314 - 316