polyzoa

Definitions

  • WordNet 3.6
    • n polyzoa marine or freshwater animals that form colonies of zooids
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Webster's Revised Unabridged Dictionary
    • n. pl Polyzoa (Zoöl) Same as Bryozoa. See Illust. under Bryozoa, and Phylactolæmata.
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Century Dictionary and Cyclopedia
    • n polyzoa The original name of one of the animais afterward grouped as Polyzoa and Bryozoa; a kind of polyzoan or bryozoan.
    • polyzoa A class of molluscoid invertebrated animals; the moss-animalcules, seamosses, or sea-mats. They are invariably compound, forming aggregated or colonial organisms originating by germination from a single parent polyzoön, and inhabit a polyzoary or polyzoarium comparable to the polypary or polypidom of a compound hydrozoan. (See polypary.) The individual or person of such a stock is called a polypide, and differs from the polypite of a cœlenterate in having a complete and distinct alimentary canal suspended freely in a body-cavity or cœloma, and in many other respects. There are definite oral and anal apertures, not communicating directly with the perivisceral cavity. The mouth is within an oral disk or lophophore supporting a circlet of ciliated tentacles, the lophophore being comparable to the wheel-organ of rotifers. The intestine is bent on itself toward the oral end of the body, bringing the anus near the mouth, either within or without the circlet of lophophoral tentacles, whence the terms entoproctous and ectoproctous. There is a well-defined nervous system, the nerve-ganglion being situated in the reëntering angle of the alimentary canal, between the mouth and the anus. The respiratory system is represented by the ciliated tentacles exsertile from the body-sac. There is no heart. The Polyzoa are hermaphrodite, and the sexual organs are contained within the body-walls. Besides the true sexual reproduction, and propagation by budding or gemmation, they exhibit in many cases a process of discontinuous gemmation. These creatures are chiefly marine, and are found incrusting submerged stones, shells, wood, seaweed, and other objects; but some inhabit fresh water. There is great diversity in size, form, and outward aspect. Some resemble corals, or polyps of various kinds, and all were confounded with various cœlenterates under the name of corallines. Though quite definite as a class, the systematic position of the Polyzoa has been much disputed. Besides having been classed as radiates, zoophytes, and polyps, they have been regarded
    • polyzoa In Protozoa, the polyzoan radiolarians: another name of the Polycyttaria or Collozoa.
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Chambers's Twentieth Century Dictionary
    • n.pl Polyzoa pol-i-zō′a a class of animals forming a crust on stones, shells, &c. under water
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Etymology

Webster's Revised Unabridged Dictionary
NL., fr. Gr. poly`s many + zo^,on an animal
Chambers's Twentieth Century Dictionary
Gr. polys, many, zōon, an animal.

Usage

In literature:

Certain compound animals, or zoophytes, as they have been termed, namely the Polyzoa, are provided with curious organs called avicularia.
"On the Origin of Species" by Charles Darwin
It appears sometimes to be parasitic upon other polyzoa, and is then much smaller.
"Narrative Of The Voyage Of H.M.S. Rattlesnake, Commanded By The Late Captain Owen Stanley, R.N., F.R.S. Etc. During The Years 1846-1850. Including Discoveries And Surveys In New Guinea, The Louisiade Archipelago, Etc. To Which Is Added The Account Of Mr. E.B. Kennedy's Expedition For The Exploration Of The Cape York Peninsula. By John Macgillivray, F.R.G.S. Naturalist To The Expedition. In Two Volumes. Volume 1." by John MacGillivray
CLASS I. POLYZOA ("Sea-Mosses").
"The Ancient Life History of the Earth" by Henry Alleyne Nicholson
Yet the echinus can have, at the best, none but the most distant genetic relationship with the Polyzoa.
"On the Genesis of Species" by St. George Mivart
Harmer in Polyzoa (1893).
"Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 3" by Various
Of the sponges and polyzoa of Ceylon we know as yet too little to make it profitable to discuss their affinities.
"Freshwater Sponges, Hydroids & Polyzoa" by Nelson Annandale
There are two divisions of the Polyzoa, the Ectoprocta and the Endoprocta.
"Stories of the Universe: Animal Life" by B. Lindsay
Corallines (bryozoa, polyzoa, &c.), cephalopods (e.g.
"Encyclopaedia Britannica, 11th Edition, Volume 16, Slice 6" by Various
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