Stage 2
Day 2
No body torsion has occurred 1^st and 2^nd brachial arches present.

Stage 3
Day 3
No body torsion. Buds present but lacks somites. Three brachial arches present.

Stage 6
Day 6
Hindlimb buds are just visible. No forelimbs present. Body torsion complete. Tail tip starting to curl.

Stage 7
Day 7
Three brachial arches. Tail tip is curled at approximately 90-degrees. Hindlimb is distinct. Forelimb bud is just visible as an elevation.

Stage 9
Day 9
Limb buds present; hindlimb, bud longer than forelimb. Tail tip curled: three 90-degree rotations. Eye non-pigmented. Four-brachial arches. Heart: distinct through pericaridal sac.

Stage 10
Day 10-11
Eye pigment light black. Five brachial arches. Hindlimb bud is fan shaped. Tail curled through four 90-degree turns.

Stage 11
Day 12
Eye pigmented. Right eye pigmented earlier and heavier than left. See chart above for limb description. Tail is curled through four 90-degree turns.

Stage 13
Day 15
Nasal pit slits very distinct. Forelimb bent towards pericardium. Hindlimb is flattened and enlarged into a footplate.

Stage 14
Day 16-17
Nasal pit slit closed. Internal nares distinct. Foot and hand plates distinct. Lower jaw extends one-fourth the upper.

Stage 15
Day18-20
Lower jaw is 1/3 to 1/2 the length of the upper jaw. Distinct hand and foot plates but no digit rays

Stage 16
Day 21
Faint digital condensations in foot but not on hand. Lower jaw 2/3 the length of upper.

Stage 17
Day 22-23
Condensations of digits. Head is extended off the bulge of the pericardial sac. Eye has a dark pigmentation. Lower jaw lies just behind the primary palate.

Stage 18
Day 24-26
Digit rays are distinct on hand and foot. Lower jaw lies beneath the anterior primary palate. Pericardial sac is starting to submerge into the thoracic wall.

Stage 19
Day 27-28
Eyelids distinct. Interdigital clefting has begun. External genitalia a globular swelling.

Stage 20
Day 29-30
Lower jaw is in adult relationship to lower. External genitalia pointed w/ distinct elevation. Scale formation dorsally. Scutes beginning to appear in neck region.

Stage 21
Day 31-35
Interdigital clefting extends 3/4 along the digits. Scales are now visible dorsally and along the tail. Pericardial sac is 1/2 withdrawn into the body cavity. A white ring in the iris surrounds the outline of the lens.
Upper and lower eyelids present

Stage 22
Day 36-40
Pigmentation on margins of the upper jaw and on proximal and distal elements of the limbs. Little or no dorsal pigmentation. Interdigital clefting is at adult level. Scalation is difficult to see on limbs.

Stage 23
Day 41-45
Pigmentation is more extensive embryos are light brown. Stripes present dorsally. Pigment present ventrally and on all limbs. Scales present on limbs.

Stage 24
Day 46-50
Pigmentation is now denser; appears blacker in color. Nails have elevations on the tip. Large amount of yolk outside body. Scales and scutes are evident.

Stage 25
Day 51-60
Considerable volume of yolk. Hooking of nails evident. Pigmentation is dark over entire body. Scales and scutes are more prevalent.

Stage 27
Day 60-63
Yolk is starting to withdraw in abdominal cavity

Stage 28
Day 64-70
Yolk scar diminishes in length and width