Pollen-storer. Nests are mainly constructed at various depths in the soil, although some sheltered nest sites are above the ground ( for example, in cavities in walls, in drain pipes, and in lofts and under roofs). The specific name "lapidarius" alludes to the species occasional habit of nesting under stones. Sladen (1912) describes the cells as having a neat and clean appearance. The wax is a pale yellowish brown, lighter in colour than that of any other British species. It is produced in great quantity and the bees work it skilfully into thin sheets and cells. The cocoons are pale yellow. Large colonies are occasionally produced (Peeters, Raemakers & Smit (1999) suggest as many as 100-300 offspring). Occupied nests are illustrated by Sladen (1912), Alford (1975) and Westrich (1989).