1. Comparative biological data in two closely related eusocial species:Evylaeus calceatus (Scop.) andEvylaeus albipes (F.) (Hym., Halictinae)

   • C. Plateaux-Quénu

   Research Articles Pages: 351 - 364

2. Super and half-sister discrimination by honey bee workers (Apis mellifera L.) in a trophallactic bioassay

   • R. F. A. Moritz
   • T. Heisler

   Research Articles Pages: 365 - 372

3. The labial gland in the termiteSchedorhinotermes lamanianus (Isoptera: Rhinotermitidae): Morphology and function during communal food exploitation

   • M. Kaib
   • J. Ziesmann

   Research Articles Pages: 373 - 384

4. Nest structure and colony cycle of the Allegheny mound ant,Formica exsectoides Forel (Hymenoptera: Formicidae)

   • C. M. Bristow
   • D. Cappaert
   • A. Heise

   Research Articles Pages: 385 - 402

5. Factors influencing seasonal absconding in colonies of the African honey bee,Apis mellifera scutellata

   • S. S. Schneider
   • L. C. McNally

   Research Articles Pages: 403 - 423

6. Social organization in some primitive Australian ants. I.Nothomyrmecia macrops Clark

   • P. Jaisson
   • D. Fresneau
   • A. Lenoir

   Research Articles Pages: 425 - 438

7. Annual life cycle and timing of male-egg production in the antColobopsis nipponicus (Wheeler)

   • E. Hasegawa

   Research Articles Pages: 439 - 446

8. An environmentally determined polymorphism in malate dehydrogenase isozymes ofMyrmica rubra as revealed by isoelectric focusing

   • A. F. Raybould
   • B. Pearson

   Short Communication Pages: 447 - 450

9. Forager success increases with experience inPolybia occidentalis (Hymenoptera: Vespidae)

   • S. O'Donnell
   • R. L. Jeanne

   Short Communication Pages: 451 - 454

10. Division of labour between foraging workers of the ponerine antPachycondyla caffraria (Smith) (Hymenoptera: Formicidae)

    • C. Agbogba
    • P. E. Howse

    Short Communication Pages: 455 - 458

11. Acknowledgements

    Acknowledgments Pages: 459 - 459