Figure 4.

(A) Surface rendering of air and the septal center surfaces (cS, as in Figure 3B) here colored such that the surface is blue inside tissue and red inside the ACN, i.e., the red regions are the intersection of the cS with the ACN. The air surface is rendered in transparent gray. (B) Surface rendering of air (transparent gray), the center surfaces (cS, as in A) and the ACN, which is arbitrarily colored such that each side (in regard to cS) has a different color. (C) Same as (B) but without the cS, instead the vein in blue (partially contained in the back). This view allows to distinguish the single-layered ACN toward the vein and the double-layered ACN mostly in septa separating sacculi. (D) Similar to (B,C) but viewed from a side, intransparent gray for the air surface to highlight the splitting of the double-layered ACN.