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Related to Peristomium: pygidium, Epitoky


n.1.Same as Peristome.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.
References in periodicals archive ?
Nuchal organs densely ciliated and extending dorso-laterally between prostomium and peristomium. Salivary glands extending to segment 12.
The anterior of the body has peristomium, fewer segments are made a thick band called as clitellum and remaining of body after clitellum is called as abdomen.
Cerebral ocelli are defined here as being located in close association with the brain, within the peristomium or prostomium (excluding the radioles).
The peristomium consists of one or two achaetous rings (Blake, 1996; Glasby, 2000; SolisWeiss et al., 2009).
Prostomium closed epilobic, covering 1/2-1/3 of peristomium. Secondary annulation characterized by a single furrow, more evident in pre-clitellar segments.
purpuratus immediately after they were stranded, and a week later they still scavenged desiccated remains of the sea urchins, usually by removing tissue through the peristomium (Ralston, pets.
Dorsal blood vessel arises in XV (sometimes afore?), proceeds forward between intestinal wall and chloragogen layer, and bifurcates between brain and pharynx in peristomium; the branches join forming ventral vessel in IV.
number of anterior asetigerous segments, Laubier (1963) reported two for Cossura soyeri Laubier, 1963, naming the anterior one as the buccal segment or peristomium. This statement disagrees with that outlined by Eliason (1920) and Thulin (1921), according to Jones (1956), who mentioned that the prostomium had a transverse furrow, giving the erroneous impression that the proximal part was an asetigerous segment.
He described a pair of exocrine glands embedded in the subepithelial connective tissue of the ventro-lateral peristomium under the fold of the collar in Ficopomatus enigmaticus (Fauvel, 1923) (as Mercierella).
The prostomium is conical and shorter or equal to its base at the peristomium. Anterior segments II through XII become progressively longer.