Bull. soc. ent.
In order to ascertain how many bees were working in a nest, Aptel plug the entrance, opening it in order to allow each returning bee to enter, but not allowing any to leave. When all of the bees had entered, he opened the nest and counted seven bees. These all left and came back one by one loaded with pollen. Then he dug open the nest and found eight cells which were scattered at the ends of random bifurcations of the gallery. Seven cells had pollen and one of these had an egg, the eighth cell was empty. It is evident that each bee constructs its own cell and provisions it independently, the empty eight cell being the second cell started by the bee which had laid the only egg in the nest. This group of cells was at depth of 50 cms. Deeper down he found cells with young bees with two pupae. These belonged to the same generation as the more precocious individuals who were building the upper cells. The deepest cell was at a depth of 70 cms.
Aptel, E., "Etude sur les ndifications de l'Halictus malachurus K. (forma longulus) generation d'ete." (1931). An. Paper 22.
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