1. Somatic hybridization of sexually incompatible petunias: Petunia parodii, Petunia parviflora

   • J. B. Power
   • S. F. Berry
   • E. C. Cocking

   OriginalPaper Pages: 1 - 4

2. The significance of genic balance to endosperm development in interspecific crosses

   • S. A. Johnston
   • T. P. M. den Nijs
   • R. E. Hanneman Jr.

   OriginalPaper Pages: 5 - 9

3. Gynodioecy as a possible populational strategy for increasing reproductive output

   • A. Horovitz
   • A. Beiles

   OriginalPaper Pages: 11 - 15

4. Book reviews

   • B. Kaina
   • E. Günther
   • H. F. Linskens

   BookReview Pages: 16 - 16

5. The effect of positive assortative mating at one locus on a second linked locus

   • H. Gregorius

   OriginalPaper Pages: 17 - 24

6. Long-term selection for a quantitative character in large replicate populations of Drosophila melanogaster

   • B. H. Yoo

   OriginalPaper Pages: 25 - 32

7. Effect of temperature on membrane fluidity and protoplast fusion

   • M. Senda
   • H. Morikawa
   • Y. Yamada

   OriginalPaper Pages: 33 - 35

8. Competitive ability of maize pollen. Intergametophytic effects

   • M. Sari Gorla
   • E. Rovida

   OriginalPaper Pages: 37 - 41

9. Book reviews

   • W. Hennig
   • H. Brandsch
   • H. F. Linskens

   BookReview Pages: 42 - 42

10. Diallel analysis of heading date in rice (Oryza sativa L.)

    • S. L. Dwivedi
    • K. N. Rai
    • R. B. Singh

    OriginalPaper Pages: 43 - 47

11. Book reviews

    • H. Brandsch
    • E. Weber
    • H. F. Linskens

    BookReview Pages: 48 - 48