File:PZSL1889Plate46.png

1. Chicken embryo, 6 days old, transverse section of lung region
2. Chicken embryo, 6 days old, transverse section of heart region
3. Viviparous Lizard embryo, transverse section of lung region
4. Mammal embryo, transverse section of lung region
5. Chicken embryo, 7 days old, transverso-horizontal section of shoulder region, magnification × 20
6. Chicken embryo, 7 days old, transverso-horizontal section of head region, magnification × 20
7. Chicken embryo, 7 days old, transverso-horizontal section of tail region, magnification × 20
8. Chicken embryo, 9 days old, longitudinal horizontal section of dorsal region seen from ventral, magnification × 9
9. Chicken embryo, 9 days old, longitudinal horizontal section of middle region seen from ventral, magnification × 9
10. Chicken embryo, 9 days old, longitudinal horizontal section of ventral region seen from ventral, magnification × 9
11. Chicken embryo, 10 days old, longitudinal horizontal section of dorsal region seen from ventral, magnification × 6
12. Chicken embryo, 10 days old, longitudinal horizontal section of middle region seen from ventral, magnification × 6
13. Chicken embryo, 10 days old, longitudinal horizontal section of ventral region seen from ventral, magnification × 6

a.al = right allantoic artery, a.al' = left allantoic artery, al = alimentary canal, als = allantois, ao = aorta dorsalis, c = heart, c' = heart wall, c.w = Wolffian body, d.a = diaphragm (avian), d.c = common cardinal vein (duct of Cuvier), d.m' = ligament of Müllerian duct, dph = diaphragm (mammalian), f.w = omental foramen (foramen of Winslow), h = right liver lobe, h' = left liver lobe, m = median thoracic septum and abdominal mesentery and ligaments around alimentary canal, ml = diaphragm muscle, pa = pancreas, pc = pericardium, pro = proventriculus, pul/Pul = lung, s.a' = anterior diaphragmatic air sac, s.a'' = posterior diaphragmatic air sac, s.a''' = abdominal air sac, s.ob = oblique septum, spl = spleen, [st. = stomach cavity, st.' = stomach wall,] v.a = anterior abdominal vein (left allantoic vein), v.c.i = vena cava inferior, v.c.s = vena cava superior, v.om = right omphalo-mesenteric vein, v.om' = left omphalo-mesenteric vein, 1 = right ventral liver sac, 1' = left ventral liver sac, 2 = right pulmohepatic recess, 2' = left pulmohepatic recess, 3 = peritoneal cavity, α = pulmohepatic ligament, β = omental septum (ventral portion of posthepatic septum), γ = oblique abdominal septum (antero-dorsal portion of posthepatic septum).