|
Stage I
|
|
3.6±0.3
|
| Tunic healed |
The hole in the tunic is closed |
3.6±0.3 |
|
Stage II
|
|
8.3±0.8
|
| Anterior nerves merging |
The two anterior nerves merge |
3.6±0.3 |
| Posterior nerves merging |
The two posterior nerves merge |
3.8±0.3 |
| Posterior thickening |
There is a swelling of the posterior nerve endings |
6.2±0.2 |
| Anterior thickening |
There is a swelling of the anterior nerve endings |
6.6±0.2 |
| Pharynx healed |
The pharynx is closed |
7.4±0.6 |
|
Stage III
|
|
14.5±2.7
|
| Posterior structure |
Merged nerve thicken and form a structure |
8.8±0.2 |
| Lateral net |
Lateral connections between the anterior nerve endings |
9. 6±0.2 |
| Posterior horns |
Nerves extending anteriorly from the posterior structure |
11. 2±0.7 |
| Anteroposterior connection |
Visible neural connection between anterior and posterior, C→B transition |
14. 0±0.8 |
|
Stage IV
|
|
18.4±0.3
|
| Anteroposterior fusion |
Connections between anterior and posterior are reinforced |
16.2±0.2 |
| Ganglion |
A thin ganglion has formed |
16.8±0.7 |
| Dorsal tubercle |
A dorsal tubercle is visible |
17.8±0.3 |
| Gland |
A gland is visible |
18.3±1.0 |
