Fig. 1 in A new technique in the excavation of ground-nest bee burrows (Hymenoptera: Apoidea)

Fig. 1. Rubber refills used as tracer for excavation: (A) with graded marks, and (B) glued to each other by their extremities tracing an Epicharis fasciata nest gallery. (C) Posterior gallery excavation in of Epicharis fasciata nests in order to obtain randomly placed brood cells around the rubber refill tracer.