craniote

Brain of three craniote embryos in vertical section.

The Evolution of Man — Volume 2 Ernst Heinrich Philipp August Haeckel 1876

The lower or ventral segments, the hyposomites, corresponding to the lateral plates of the craniote-embryo, fuse together in the upper part owing to the disappearance of their lateral walls, and thus form the later body-cavity (metacoel); in the lower part they remain separate, and afterwards form the segmental gonads.

The Evolution of Man — Volume 2 Ernst Heinrich Philipp August Haeckel 1876

Our craniote ancestors had a third eye-lid, the nictitating membrane, which was drawn over the eye from its inner angle.

The Evolution of Man — Volume 2 Ernst Heinrich Philipp August Haeckel 1876

But they also are very important in connection with certain functions of the craniote-organism, especially the exchange of gases or respiration.

The Evolution of Man — Volume 2 Ernst Heinrich Philipp August Haeckel 1876

Just as to-day the intricate structure of the brain proceeds step by step from the same rudiment in every human individual -- the same five cerebral vesicles -- as in all the other Craniotes; so the human soul has been gradually developed in the course of millions of years from a long series of craniote-souls.

The Evolution of Man — Volume 2 Ernst Heinrich Philipp August Haeckel 1876

The primitive renal duct, which appears first, is found in all craniote embryos at the early stage in which the differentiation of the medullary tube takes place in the ectoderm, the severance of the chorda from the visceral layer in the entoderm, and the first trace of the coelom-pouches arises between the limiting layers (Figure 2.385).

The Evolution of Man — Volume 2 Ernst Heinrich Philipp August Haeckel 1876

(perichorda); it originates from the dorsal and median part of the coelom-pouches, which we shall call the skeleton plate or "sclerotom" in the craniote embryo.

The Evolution of Man — Volume 1 Ernst Heinrich Philipp August Haeckel 1876