Nesting Behavior of Halictus Scabiosae in Switzerland (Hymenoptera, Halictidae)

Although Halictus scabiosre (Rossi) is a conspicuous bee and fairly common in many parts of Europe, there is little detailed information regarding its nest structure and social behavior. FABRE (1915) recognized that it was a social species and discussed the life cycle and nests (as H. zebrus). The nest architecture has also been briefly discussed by GRANDI (1954) and QUENU (1954) but an unusual nest illustrated by FAHRINGER (1914) and attributed to H. scabiosre was probably not actually made by this species. Dissections of females from a single nest revealed distinct castes (QUENU, 1957). The additional material presented below emphasizes the need for a more extensive study of this primitively social bee