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Hydrozoa

Hydrozoa (hydroids; phylum Cnidaria) A class of multicellular, mainly marine animals in which the cells are derived from two layers, epidermis and gastrodermis (endodermis), separated by a gelatinous mesogloea. These enclose a continuous gastrovascular cavity (coelenteron), which communicates directly with the exterior by a single aperture (mouth) and is lined by a gastrodermis. The gastrodermis lacks nematocysts. Eggs and sperm are shed outside the animal and not into the gastrovascular cavity.

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"Hydrozoa." A Dictionary of Zoology. . Encyclopedia.com. 19 Aug. 2017 <http://www.encyclopedia.com>.

"Hydrozoa." A Dictionary of Zoology. . Encyclopedia.com. (August 19, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/hydrozoa-0

"Hydrozoa." A Dictionary of Zoology. . Retrieved August 19, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/hydrozoa-0

Hydrozoa

Hydrozoa (hydroids; phylum Cnidaria) Class of multicellular, mainly marine animals with cells arranged in two layers, the epidermis and the gastrodermis (endodermis), separated by a gelatinous mesogloea. These enclose a continuous digestive cavity (coelenteron), which communicates directly with the exterior by a single aperture (mouth) and is lined by a gastrodermis. The gastrodermis lacks nematocysts. Hydrozoa are Lower Cambrian to Recent. See also MILLEPORINA; and STYLASTERINA.

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"Hydrozoa." A Dictionary of Earth Sciences. . Encyclopedia.com. 19 Aug. 2017 <http://www.encyclopedia.com>.

"Hydrozoa." A Dictionary of Earth Sciences. . Encyclopedia.com. (August 19, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/hydrozoa

"Hydrozoa." A Dictionary of Earth Sciences. . Retrieved August 19, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/hydrozoa

hydrozoa

hydrozoa Class of animals without backbones, all living in water, belonging to the phylum Coelenterata. They vary in shape and size from the large Portuguese man-of-war to the simple hydra.

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"hydrozoa." World Encyclopedia. . Encyclopedia.com. 19 Aug. 2017 <http://www.encyclopedia.com>.

"hydrozoa." World Encyclopedia. . Encyclopedia.com. (August 19, 2017). http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/hydrozoa

"hydrozoa." World Encyclopedia. . Retrieved August 19, 2017 from Encyclopedia.com: http://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/hydrozoa

Hydrozoa

Hydrozoa See Cnidaria.

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"Hydrozoa." A Dictionary of Biology. . Encyclopedia.com. 19 Aug. 2017 <http://www.encyclopedia.com>.

"Hydrozoa." A Dictionary of Biology. . Encyclopedia.com. (August 19, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/hydrozoa-1

"Hydrozoa." A Dictionary of Biology. . Retrieved August 19, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/hydrozoa-1