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.