hydroid


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hydroid

a member of the COELENTERATE class Hydrozoa. Most are colonial forms which grow in the marine environment on rocks and seaweeds, such as Obelia. Usually, there is an ALTERNATION OF GENERATIONS (not in HYDRA) in which the MEDUSA (free-swimming) stage carries the sex organs. The sedentary, nonsexual stage of this life cycle is itself referred to as the POLYP or (less commonly) hydroid stage.
References in periodicals archive ?
Early summer (May to July) was dominated by hydroid and bivalve settlement.
The cover of hydroids, bushy bryozoans, sponges, and tubeworms was generally higher at sites undisturbed by fishing than at sites classified as disturbed.
ESS works closely with Hydroid to provide syntactic materials that support deeper depths and larger payloads without impacting power consumption.
While Hydroid operated in the English Channel about 30 miles out to sea, MASTT focused on the waters just off Slapton Sands where the Exercise Tiger beach landing took place.
With Duane managing the company, I now have the flexibility to focus on Hydroid s future technological developments, von Alt said.
Settlement of Iceland scallop Chlamys islandica spat in response to hydroids and filamentous red algae: field observations and laboratory experiments.
The Teledyne Brown team is comprised of Teledyne Marine businesses; Teledyne Scientific and Imaging; Rutgers University; Scripps Institute of Oceanography; Hydroid, Inc; and Analytical Services, Inc.
The UUV systems protect the membders of all services and the public who could be subject to danger from undetected/unidentified underwater threat objects in both foreign and domestic coastal and confined waters, says a document justifying the decisions to award the contract to Hydroid without competition.
Year and Month July October January Species Phyla 2004 2004 2005 Cliona celata Porifera - - - Unidentified hydroid Cnidaria - + + Diadumene lineata Cnidaria - + + Unidentified bryozoan Bryozoa - + + Membranipora tenuis Bryozoa - + + Boonea impressa Mollusca - + + Brachidontes exustus Mollusca + + + Crassostrea virginica Mollusca + + + Crepidula maculosa Mollusca - + + Geukensia demissa Mollusca - + + Littorina meleagris Mollusca + + + Nassarius obsoletus Mollusca + + + Sphenia antillensis Mollusca - - + Hydroides sp.
One species of bivalve, one species of hydroid, six species of crustacean, one elasmobranch, and 16 species of teleost were observed (Table 1).
Observations on adverse relations between the hydroid Hydractinia echinata, and certain molluscs.