File:Waterston20.jpg

Fig. 20. Model after removal of the septum transversum.

Wax-plate reconstruction model in fig.19, after removal of the septum transversum, showing the dorsal wall ofpericardial and peritoneal ccelom with orifices ofright and left pneumato-enteric recesses.

The dotted area indicates, above, the attachment of the dorsal mesocardium, and, below, the ventral mesentery.

Legend

• A, ducts of Cuvier
• B, mesodermal lung thickenings; orifices of pneumato-enteric recesses

Carnegie Staging Comparison: A 27 somite stage embryo would be similar to a Carnegie stage 12 (26 - 30 days), caudal neuropore closes, Somite Number 21-29.

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Historic Paper Links: 13-14 Somites | 22 Somites | 23 Somites | 25 Somites | 27 Somites | Mall Human Embryo Collection | Embryology History | Carnegie stage 11 | Carnegie stage 12 | Journal of Anatomy | Embryonic Development | Category:Historic Embryology

Reference

<pubmed>17233016</pubmed>| PMC1288995