190 
a 
V0 929) DD DIDDY 9 u: 
DL] 
q = < 
» fren A 
BA, 
P 
Av Pz <| 
Gl » § 
ex 
AA 
AW es 
A 
iA 
; 11 Pr 
; | wi 
Fig. 3. Scheme of the lung lobule. 
B. terminal bronchus; A. atrium; S. air-sac; V. vestibule; - ?. air-sac passage; 
©. air-cell. The shaded vessel is the artery, the vein is in outline. 
walls of the air-cells, air-sacs and atria. As the capillaries approach 
the peripheral side of the air-sac they join to form the venous twigs, 
which in turn unite to form the veins proper. Thus we see that we 
have an artery on the central side of each air-sac, a vein on the 
peripheral, and between the two this rich capillary net-work, thus 
giving an arterial and venous side to each air-sac. 
Frommannsche Buchdruckerei (Hermann Pohle) in Jena, 
