Fig. 3. Wave propagation in isolated slug tips. (A) Brightfield image of an isolated tip from a slug of strain NP377. The tip was separated from the prespore region with a fine syringe needle. (B) Subtracted image showing the same tip 16 minutes later. The black arrow points at the dark appearing wave front. (C) Time-space plot over the whole sequence of subtracted images. The white arrows mark five propagated waves. Scale bars: 100 µm.