Excavator: Ground. A generally gregarious species, nesting in aggregations in vertical banks, cliff faces, the sides of sand pits, cob walls and often in the mortar joints of old crumbling masonry. The nest usually consists of two or more burrows which distally contain short lengths of consecutively arranged, pitcher-shaped cells, each with a flat lid. The side walls and lids of the cells are constructed from fine, and seemingly agglutinated, soil particles. When a nest is unearthed, the cells normally maintain their integrity, being easily extracted intact from the surrounding soil substrate. A nest has been figured by O'Toole & Raw (1991). Nest construction and provisioning is described and illustrated in great detail by Malyshev (1928) and van Lith (1947). Müller, Krebs & Amiet (1997) illustrate both nests and their contents.