The Zooplankton and the Zoobenthos of the White Nile and Adjoining waters in the Republic of the Sudan A. V. Monakov OriginalPaper 01 May 1969 Pages: 161 - 185
The Determination of Nitrotase Activity in Denitrifying Systems G. Lenhard OriginalPaper 01 May 1969 Pages: 186 - 192
Determination of Urease Activity in Biological Purification Systems G. Lenard OriginalPaper 01 May 1969 Pages: 193 - 200
Liagora Visakhapatnamensis, a New species from India M. Umamaheswara Rao OriginalPaper 01 May 1969 Pages: 201 - 208
Untersuchungen über Toxizität II Experimente mit Ulothrix tenerrima Kützing K. Cholnoky-Pfannkuche OriginalPaper 01 May 1969 Pages: 223 - 236
Substrate preferences and invasion behaviour exhibited by larvae of nilodorum brevibucca freeman (Chironomidae) under experimental conditions A. J. McLachlan OriginalPaper 01 May 1969 Pages: 237 - 249
Beiträge zur Kenntnis der Algenvegetation der Natron- bzw. Soda- (Szik-) Gewässer Ungarns. II. Über die Algen des Teiches Őszeszék G. Uherkovich OriginalPaper 01 May 1969 Pages: 250 - 288