INSECTES SOCIAUX, 1989, Vol.36, No.4 1) Plateaux-Quenu C., Plateaux L., Packer L. Biological notes on Evylaeus villosulus (Hym., Halictidae), a bivoltine, largely solitary halictine bee, 245-263 CNRS, Laboratoire d'Evolution, 105 Bd Raspail, F-75006 Paris (France) 2) Huang Z.Y., Otis G.W. Factors determining hypopharyngeal gland activity of worker honey bees, 264-276 Univ. Guelph, Deprtment of Environmental Biology, Guelph Ontario N1G 2W1 (Canada ) The other papers of this issue concern ants and termites.