Hi Allen, thanks for the reply, My question was concerned with the whole range of behaviour of the colony.This may manifest itself as inability to forage effectivley due to loss of ability to orientate to the colony, or increaced defensive behavior. This was initiated by the findings that Drosophila melanogaster after ether treatment seem to have problems with orientaton. In "Drosophila a laboratory handbook" Michael Ashburner 1989 Cold spring Harbor. He mentions that even after brief treatment with ether flies have shown:- (and I quote) a dramatic long term effect..on the searching behavior of the flies. Flies were tracked in a circular arena, in the center of which was a banana odor. Control flies, congregrated around the source of the aroma. Flies that had been briefly etherised once, 4 days before the experiment, showed a very different behaviour:They had a strong aversion to the center of the arena and hugged the walls. This ether-induced "centrophobism" is apparrently permanent. My question was really to do with the effects of chemical solvent agents on the behaviour of bees in particular ether and chloroform on foraging ability. Luckily the problems I was facing, I have now overcome, but it seems that carbon dioxide is the method of choice over these solvent anaesthetics. We have a system here in my laboratory for anaethesising Drosophila, but the cylinders are huge. I have however devised a portable dry-ice driven equipment, which runs on hot water (and bubbles also through hot water to warm the gas up so that the bees don't get chilled. This is reserved for use on bees where on lifting the cover it is like running into a hailstorm of bees. I find it difficult to find queens when experiencing intense pain! Steve Pearce Dept of Biochemistry University of Dundee