G6: Rathke's pouch. Floor of pharynx with foramen caecum (remains of thyroglossal duct), and caudally to it, the hypopharyngeal eminence. Aortic sac ventral to H-P eminence. Caudal pharynx (extending laterally, ventral to dorsal aorta - cf B4). L lungbud caudal to L atrium with attachment of pulmonary mesenchyme to septum transversum. Stomach, mesentery.
G6: Liver. Gall bladder. Cranial limb of midgut loop in mesentery with intervitelline anastomoses. Caudal attachment of mesentery with hindgut inside. Communication of intra- and extra-embryonic coeloms.
G6: Cervical region (neural tube cut very obliquely): note the wavy notochord and thin roof and floor plates. Thoracic region: alternating light and dark parts of the sclerotomes (vertebral bodies and I.V. Discs, respectively). Lumbar region: tiny, dorsal segmental branches of dorsal aorta Each little branch is aligned almost parallel to the cranial border of the next caudal dorsal root ganglion (segmented dark masses). Sacral region: oblique section of neural tube, notochord.
The Carnegie stage 13/14 Pig Embryo is 6mm in size and approximately equal to day 42 Human Embryo. Use the serial images to identify internal features and relationships that exist within the embryo at this stage. Then compare these images with the external appearance of the embryo at this stage and the later internal features of the stage 22 embryo.
Note that the nomenclature "stage 13/14" is not an actual Carnegie stage but indicates that the embryo stage lies between or has features of both stage 13 and stage 14 embryos.
Levels shown on whole embryo are only approximate.
Note that not all embryo features are labelled.
Hint: clicking on each section image above will also step you through the whole embryo in sequence.