Template:Hamburger Hamilton stages table
From Embryology
3.5-4.5 hr | Shell membrane of egg formed in isthmus of oviduct | ||
Germ wall formed from marginal periblast | |||
4.5-24.0 hr | Shell of egg formed in uterus | ||
Preprimitive streak (embryonic shield) | |||
6-7 hr | Initial primitive streak, 0.3-0.5 mm long | ||
12-13 hr | Intermediate primitive streak | ||
18-19 hr | Definitive primitive streak, ± 1.88 mm long | ![]() | |
19-22 hr | Head process (notochord) | ![]() | |
23-25 hr | Head fold | ![]() | |
23-26 hr | 1 somite; neural folds | ![]() | |
ca. 23-26 hr | 1-3 somites; coelom | ||
26-29 hr | 4 somites; blood islands | ![]() | |
29-33 hr | 7 somites; primary optic vesicles | ![]() | |
ca. 33 hr | 8-9 somites; anterior amniotic fold | ||
33-38 hr | 10 somites; 3 primary brain vesicles | ![]() | |
40-45 hr | 13 somites; 5 neuromeres of hindbrain | ![]() | |
45-49 hr | 16 somites; telencephalon | ![]() | |
48-52 hr | 19 somites; atrioventricular canal | ![]() | |
ca. 50-52 hr | 20-21 somites; tail bud | ![]() | |
50-53 hr | 22 somites; trunk flexure; visceral arches I and II, clefts 1 and 2 | ![]() | |
ca. 50-54 hr | 23 somites; premandibular head cavities | ||
50-55 hr | 24-27 somites; visceral arch III, cleft 3 | ![]() | |
51-56 hr | 26-28 somites; wing bud; posterior amniotic fold | ![]() | |
52-64 hr | 29-32 somites; leg bud; epiphysis | ![]() | |
3 da | 30-36 somites extending beyond level of leg bud; allantois | ![]() | |
3.0-3.5 da | 37- 40 somites extending into tail; maxillary process | ![]() | |
3.0-3.5 da | 40-43 somites; rotation completed; eye pigment | ![]() | |
3.5 da | 43-44 somites; visceral arch IV, cleft 4 | ![]() | |
3.5-4.0 da | Somites extend to tip of tail | ![]() | |
4 da | Dorsal contour from hindbrain to tail is a curved line | ![]() | |
4.5 da | Toe plate | ![]() | |
4.5-5.0 da | Elbow and knee joints | ![]() | |
5 da | 1st 3 toes | ![]() | |
5.0-5.5 da | Beak | ![]() | |
5.5-6.0 da | 3 digits, 4 toes | ![]() | |
6.0-6.5 da | Rudiment of 5th toe | ![]() | |
6.5-7.0 da | Feather germs; scleral papillae; egg tooth | ![]() | |
7.0-7.5 da | Web between 1st and 2nd digits | ![]() | |
7.5 da | Anterior tip of mandible has reached beak | ![]() | |
7.5-8.0 da | Web on radial margin of wing and 1st digit | ![]() | |
8 da | Nictitating membrane | ![]() | |
8.5-9.0 da | Phalanges in toes | ![]() | |
10 da | Length of 3rd toe from tip to middle of metatarsal joint = 5.4 ± 0.3mm; length of beak from anterior angle of nostril to tip of bill = 2.5mm; primordium of comb; labial groove; uropygial gland | ![]() | |
11 da | Length of 3rd toe = 7.4 ± 0.3mm; length of beak = 3.0 mm | ![]() | |
12 da | Length of 3rd toe = 8.4 ± 0.3 mm; length of beak = 3.1 mm | File:HHstage38.jpg | |
13 da | Length of 3rd toe = 9.8 ± 0.3 mm; length of beak = 3.5 mm | File:HHstage39.jpg | |
14 da | Length of beak = 4.0 mm; length of 3rd toe = 12.7 ± 0.5 mm | ||
15 da | Length of beak from anterior angle of nostril to tip of upper bill = 4.5 mm; length of 3rd toe = 14.9 ± 0.8 mm | ||
16 da | Length of beak = 4.8 mm; length of 3rd toe = 16.7 ± 0.8 mm | ||
17 da | Length of beak = 5.0 mm; length of 3rd toe = 18.6 ± 0.8 mm | ||
18 da | Length of beak = 5.7 mm; length of 3rd toe = 20.4 ± 0.8 mm | ||
19-20 da | Yolk sac half enclosed in body cavity; chorio-allantoic membrane contains less blood and is "sticky" in living embryo | ||
20-21 da | Newly-hatched chick |