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Webster’s Dictionary (1828)

98,828 entries. Headwords are matched first, then definition text.

15 words match “ANNELIDA”

A division of the Articulata, having the body formed of numerous rings or annular segments, and without jointed legs. The principal subdivisions are the Chætopoda, including the Oligochæta or earthworms and Polychæta or marine worms; and the Hirudinea or leeches. See Chætopoda.

ANNELID; ANNELIDAN a. 2 definitions

Of or pertaining to the Annelida. -- n.

ARCHIANNELIDA n.

A group of Annelida remarkable for having no external segments or distinct ventral nerve ganglions.

A class of articulate animals, nearly equivalent to Annelida, including the marine annelids, earthworms, Gephyrea, Gymnotoma, leeches, etc. See Annelida.

A very extensive order of Annelida, characterized by the presence of lateral setæ, or spines, on most or all of the segments. They are divided into two principal groups: Oligochæta, including the earthworms and allied forms, and Polychæta, including most of the marine species.

CIRRUS n. 2 definitions

A soft tactile appendage of the mantle of many Mollusca, and of the parapodia of Annelida. Those near the head of annelids are Tentacular cirri; those of the last segment are caudal cirri.

DORSIBRANCHIATA n.

h the branchiæ are along the back, on each side, or on the parapodia. [See Illusts. under Annelida and Chætopoda.]

A division of Annelida which includes the genus Echiurus and allies. They are often classed among the Gephyrea, and called the armed Gephyreans.

An order of marine Annelida, in which the body is imperfectly, or not at all, annulated externally, and is mostly without setæ.

A group of transparent, free-swimming Annelida, having setae only in the cephalic appendages.

An order of Annelida, including the leeches; -- called also Hirudinei.

An order of Annelida which includes the earthworms and related species.

e for its simplicity of structure and want of parapodia. It is the type of the order Archiannelida, or Gymnotoma. See Loeven's larva.

An extensive division of marine Annelida, including those that are without oral tentacles or cirri, and have the gills, when present, mostly arranged along the sides of the body. They generally live in burrows or tubes.