Figure 4
SEM imaging of corrosion casted control trachea. (A) External surface showing longitudinal vessels (LV) that give off circumferential branches (CB) connected by vertical branches (VB) that course deeply to form a dense capillary plexus. (B) The lumenal surface is an interconnected mesh of capillaries with vessel buds, sprouts, and intussusceptions. Hypoxic or degenerative features are not visible.