Illustration of the Still-air olfactometers used to investigate bed bug behaviour. Illustration of the Still-air olfactometers used to investigate bed bug behaviour. (A) Still-air olfactometer I, internal diameter 140 mm, hole diameter 26 mm, distance between holes 64 mm, distance to edge 12 mm. (B) Still-air olfactometer II, internal diameter 190 mm, hole diameter 26 mm, distance between holes 64 mm, distance to edge 32 mm. Pots were plastic and measured 60×40 mm (height × diameter). Odour pot contained bed bug-exposed paper. No-odour pot contained clean unexposed filter paper. E. N. I. Weeks et al. J Exp Biol 2013;216:460-469 © 2013.