Fig. 25. Through anterior part of trunk.
Figs. 26-27. Transverse[TN20] sections of the head of an embryo on the sixth day after impregnation.
Fig. 26. Through fore-brain and optic vesicles.
Fig. 27. Through hind-brain and auditory pits.
Plate 36.
Figs. 28-29. Transverse sections of the trunk of an embryo on the sixth day after impregnation.
Fig. 28. Through anterior part of trunk (from a slightly older embryo than the other sections of this stage).
Fig. 29. Slightly posterior to fig. 28, shewing formation of segmental duct as a fold of the somatic mesoblast.
Fig. 30. Longitudinal horizontal section of embryo on the sixth day after impregnation, passing through the mesoblastic somites, notochord, and medullary canal.
Figs. 31-34. Transverse sections through an embryo on the seventh day after impregnation.