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Cryptogamic vegetation would have the advantage over Phanerogamic; Hydrozoa over Corals; Crustacea over Insecta, and Amphipoda and Isopoda over the higher Crustacea; Cetaceans and Seals over the Primates; the civilisation of the Esquimaux over that of the European.

Huxley, in describing the development of the Hydrozoa the endoderm and ectoderm. This primary division marks out a fundamental contrast of parts in the future organism. From the mucous layer, or endoderm, is developed the apparatus of nutrition; while from the serous layer, or ectoderm, is developed the apparatus of external action.

But, though with much difficulty the scientific authorities enabled him to secure the promised Government grant for his book, and a temporary billet ashore while he worked at it, he was only able to publish his Oceanic Hydrozoa; a vast quantity of his researches remained unpublished, and subsequent investigators, going over the same ground, won the credit for them.

Cryptogamic vegetation would have the advantage over Phanerogamic; Hydrozoa over Corals; Crustacea over Insecta, and Amphipoda and Isopoda over the higher Crustacea; Cetaceans and Seals over the Primates; the civilization of the Esquimaux over that of the European.

Cryptogamic vegetation would have the advantage over Phanerogamic; Hydrozoa over Corals; Crustacea over Insecta, and Amphipoda and Isopoda over the higher Crustacea; Cetaceans and Seals over the Primates; the civilization of the Esquimaux over that of the European.

Returning to the Hydrozoa, we observe that in the simplest of the compound forms the connected individuals are alike in structure, and perform like functions; with the exception that here and there a bud, instead of developing into a stomach, mouth, and tentacles, becomes an egg-sac. But with the oceanic Hydrozoa this is by no means the case.

This process being from time to time repeated, an extensive region is at length occupied by numerous tribes descended from a common ancestry. The analogy by no means ends here. Though in the common Hydra the young ones that bud out from the parent soon become detached and independent; yet throughout the rest of the class Hydrozoa, to which this creature belongs, the like does not generally happen.

COELENTERATES. This subkingdom includes two classes of interest to the geologist, the HYDROZOA, such as the fresh-water hydra and the jellyfish, and the CORALS. Both classes existed in the Cambrian. The Hydrozoa were represented not only by jellyfish but also by the GRAPTOLITE, which takes its name from a fancied resemblance of some of its forms to a quill pen.

The oceanic Fauna is not a rich one; its hydrozoa do not admit of preservation; and the hard parts of its few kinds of molluscs and crustaceans and insects are mostly fragile.

Cryptogamic vegetation would have the advantage over Phanerogamic; Hydrozoa over Corals; Crustacea over Insecta, and Amphipoda and Isopoda over the higher Crustacea; Cetaceans and Seals over the Primates; the civilization of the Esquimaux over that of the European.