Century Dictionary and Cyclopedia
- The annelids or Annelides, a class of invertebrate animals, of the phylum Vermes, sometimes called the class of red-blooded worms. The body is composed of numerous (up to some 400) segments, somites, or metameres, and limbs are wanting, or, if present, are rudimentary and consist of the cilia or setæ known as parapodia. A vascular system with red blood is usually present; the integument is soft, and composed of many layers, the surface being mostly ciliate or setose; the head is wanting or rudimentary, and in the latter case consists of a prostomium which may be cirriferous or tentaculiferous. The Annelida are the “worms,” properly so called, of which the common earthworm, lobworm, and leech are characteristic examples. Most of the species are aquatic and marine. The class is differently limited by different authors, the principal variation among later writers, however, being in excluding or including the Gephyrea. Excluding these, as is done by the above definition, the Annelida have been divided into four orders: Hirudinea, Discophora, or Suctoria, the leeches;
- In Huxley's system (1877), a superordinal division including the Polychœta, Oligochœta, Hirudinea, and Gephyrea, with the Myzostomata doubtfully added thereto: a group the members of which resemble one another generally in the segmentation of the body indicated at least by the serially multiganglionate nervous centers (wanting in most Gephyrea), in the presence of cilia and segmental organs, and in the nature of the larvæ, which are set free when the embryos hatch.
GNU Webster's 1913
- n. (Zoöl.) 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.
- n. segmented worms: earthworms; lugworms; leeches.
- Latin anellus, little ring (Wiktionary)
“Maybe five year olds, the ones troweling up dirt, practicing the long-forgotten art of making mud pies, daring each other to snort an earthworm for that Annelida high.”
“Arthropoda for 150 years were believed to originate from Annelida, but now they are derived from Nematoda.”
“Of the phyla you haven't seen alive, I have seen: Chaetognatha, Nematomorpha, Nemertea, Sipuncula, Echiura which is really a subgroup of Annelida, Phoronida and Brachiopoda.”
“In fact, there are so many species of beetles that there are more species of beetles than the total number of species currently living in the Phyla Echinodermata, Mollusca, Annelida, Platyhelminthes, Cnidaria, and Porifera combined!”
“Megascolides australis phylum Annelida is truly a giant among terrestrial invertebrates; according to this document lengths of adults average under 1 m.”
“The main assumption was that the neural or blastoporal surface must be homologous throughout the Metazoa, though it was dorsal in the Chordata, ventral in the Annelida and Arthropoda.”
“At this time he considered _Balanoglossus_ -- by reason of its gill-slits (its notochord he did not know) -- to be the nearest living representative of the ancestral form of Vertebrates and Annelida.”
“Geoffroy's principle of the unity of plan and composition to the three great metameric groups, the Annelida, Arthropoda, and Vertebrata.”
“Having established this primary principle, Semper has little difficulty in showing that the main organs of the body lie to one another in the same relative positions in Annelida, Arthropoda, and Vertebrata; and this, together with the metameric segmentation common to them all, constitutes his first great argument in favour of their genetic relationship.”
“The characteristic relation of the central nervous system to the blastopore in Annelida and Vertebrates had already been pointed out by”
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