1. On principles of organization of polyreplicon systems

   • V. A. Ratner
   • V. A. Kulitchkov

   OriginalPaper Pages: 145 - 150

2. Age-related variation in genetic control of height growth in Douglas-fir

   • G. Namkoong
   • R. A. Usanis
   • R. R. Silen

   OriginalPaper Pages: 151 - 159

3. Studies on induced mutants with reference to species relationships in some tetraploid Triticums

   • M. V. R. Prasad

   OriginalPaper Pages: 160 - 167

4. Heritability of some characters of rye under open pollination

   • Tadeusz Wolski
   • Jerzy Brykczynski
   • Ewa Tymieniecka

   OriginalPaper Pages: 168 - 173

5. Quantitative variability in wheat following irradiation, EMS, and hybridization

   • F. H. Khadr
   • M. W. Shukry

   OriginalPaper Pages: 174 - 180

6. Relative sterol composition in the genus Nicotiana

   • Amber L. S. Cheng
   • S. J. Sheen

   OriginalPaper Pages: 181 - 186

7. A „Haploids Information Service” (HIS)

   Brief Notice Pages: 187 - 187

8. Book reviews

   • Bickel
   • A. J. Müller
   • Kh. Lohs

   BookReview Pages: 187 - 188