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| | The Oceanic Hydrozoa (1858) |
 | | The cilia of the endoderm, aided by the contractions of the walls of the body, are the sole means provided by nature for the circulation of the nutritive fluid in the Hydrozoa; the cilia of the ectoderm, similarly aided by contractility, constitute the only respiratory mechanism. |
| | Notwithstanding the extreme variety of form exhibited by the Hydrozoa, and the multiplicity and complexity of the organs which some of them possess, they never lose the traces of this primitive simplicity of organization; and it is but rarely that it is even disguised to any considerable extent. |
| | And every organ of a Hydrozoon is produced by budding from one, or other, or both, of these primitive membranes; the ordinary case being, that the new part commences its existence as a papillary process of both membranes, including, of course, a cæcal diverticulum of the somatic cavity. |
| aleph0.clarku.edu /huxley/Book/OcHydr.html (2175 words) |
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