1. Pleuroxus (Chydoridae): Field observations and growth

   • N. N. Smirnov
   • Н. Н. Смирнов

   OriginalPaper 01 June 1964 Pages: 305 - 320

2. Desmidiaceen aus Brasilien

   • Kurt Förster

   OriginalPaper 01 June 1964 Pages: 321 - 505

3. Evidence of a spring rise in metabolic rate in the burrowing mayfly ephemera simulans Walker

   • C. H. Eriksen

   OriginalPaper 01 June 1964 Pages: 506 - 510

4. A new variety of Nitzschia sinuata (W. Sm.) Grun. from North Wales, Great Britain

   • S. Biswas

   OriginalPaper 01 June 1964 Pages: 511 - 514

5. A bio-ecologial study of Nuggikari lake in Dharwar, Mysore State, South India

   • Indira Jayangoudar

   OriginalPaper 01 June 1964 Pages: 515 - 532

6. Some factors affecting the respiration of some aquatic plants

   • M. Owens
   • P. J. Maris

   OriginalPaper 01 June 1964 Pages: 533 - 543

7. Bostrychia hamana-tokidaï post synoptische studie

   • Erika Post

   OriginalPaper 01 June 1964 Pages: 544 - 560

8. Dr. h. c. Georg Ulmer Nachruf

   • F. Lenz

   Announcement 01 June 1964 Pages: 561 - 573

9. Leo Minder 1887–1961

   • K. Wurhmann

   Announcement 01 June 1964 Pages: 574 - 576

10. In memoriam Dr A. G. Vorstman

    Legacy 01 June 1964 Pages: 577 - 581

11. Libri novi

    • P.v.O.

    BookReview 01 June 1964 Pages: 582 - 583

12. Bibliography

    Legacy 01 June 1964 Pages: 584 - 589

13. Recommandation No 3

    Legacy 01 June 1964 Pages: 590 - 590