Figure 31–33: Matrigel cultured preparations of developing chicken lungs showing effect of FGF-10 soaked in beads (arrows) on the developing secondary bronchi (asterisks) between days 6 (Figures 31, 32) and 10 (Figure 33) of embryonic life: Figure 32 is an enlarged view of the area enclosed in Figure 31. The secondary bronchi (asterisks) are seen growing towards and surrounding the bead. PB, primary bronchus; Pr, parabronchi. Scale bars: Figure 31, 200 μm; Figure 32, 100 μm; Figure 33, 100 μm. From unpublished work done by JN Maina and B Kramer.