Fig. 2. Lung surface and pulmonary pleura at the saccular phase in late stage fetuses. H&E staining. Sagittal sections. Panels A and B display the left lung from a specimen at 26 weeks (215 mm crown-rump length [CRL]), while panels C and D exhibit the right lung from a specimen at 31 weeks (255 mm CRL). The subpleural tissue (stars) is thicker in the basal area than in the upper area near the apex of the lung and it contains dilated superficial veins those connected with deep, intersegmental veins. All panels were prepared at the same magnification. Scale bar=1 mm (A).