Cestoidea
Century Dictionary and Cyclopedia
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- cestoidea An order of platyhelminths or flatworms, having no intestinal cavity; the tapeworms; Tæniata or Agastreæ. They are internal parasites, without digestive or blood-vascular systems, hermaphrodite, mostly of an elongated and flattened form, like a piece of tape, and with the anterior end of the body, or head, provided with hooks, suckers, spines, or other armature for adhering. In the typical forms the animal is segmented, and in the tapeworm Tænia solium there may be as many as 800 joints; but the head alone is the true animal, the joints or proglottides being merely hermaphroditic reproductive organs budded from the head. The embryo is called a proscolex, and at a later stage a scolex; in the encysted state the animals are known as hydatids. The chain of reproductive segments is the strobila. There are several families of cestoids, as the Tæniidæ, Dibothriidæ, Diphyllidæ, Tetraphyllidæ, Tetrarhynchidæ, and Caryophyllædæ. Also called Cestoda.
- cestoidea A group of tentaculate Ctenophora having a compressed, bandlike body and containing the single family Cestidæ.
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Webster's Revised Unabridged Dictionary
NL., gr. Gr. kesto`s girdle + -oid,