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ordering of cortical structure(s) to be determined by the preexisting organization of the cytoplasm in the particular site concerned; the ordering and arrang- ing of new cell structure under the influence of pre-existing cell structure; see also Structural Guidance Principle . D Dactylophrya \u2013 Stage : see Dactylozoite . Dactylozoite : infective stage in the most unusual life cycle of the suctorian Tachyblaston ; dactylozoi- tes arise by several rapid fissions of the loricate parental organism, and then, though non-ciliated and with but one tentacle, reach the body of another suctorian, Ephelota , \u201cburrow\u201d in, and develop into forms producing a ciliated swarmer stage; swarmers settle down, often on the stalk of the same Ephelota , produce their own stalk and lorica, and repeat the cycle; a synonym is Dactylophrya -stage. Dargyrome : argyrome on the dorsal surface of hypotrich spirotrichs. Daughter Organisms : see Filial Products . Deme : population within a species; the concept is particularly used by parasitologists to indicate popu- lations of different types: (e.g. monodeme, nosodeme, serodeme, topodeme, and xenodeme); the organisms comprising different demes may possess distinctive morphological and/or physiological characters and, in some cases, may be incipient subspecies or even unrecognized biological species. Dendritic Colony : synonym of arboroid colony . Dendroid Colony : synonym of arboroid colony . De Novo Cytoplasmic : now discarded term for a mode of stomatogenesis ; see Telokinetal for its modified replacement. De Novo Kinetosomal : now discarded term for a mode of stomatogenesis ; see Apokinetal . Denticle : one of many similar structures or inter- locked component parts of a supporting ring under- lying the adhesive disc of mobiline peritrichs; a proteinaceous subpellicular skeletal element composed of a conical centrum and typically an inwardly directed spine or ray and outwardly directed blade (Dent, Fig. 2.9Bg, 2.9Bh). Denticulate Ring : skeletal organelle, made up of denticles , found in mobiline peritrichs ; see Denticle (Fig. 2.4L). Derived Character : see Apomorphy . Desmodexy, Rule of : true kinetodesmata , when present, lie to or extend anteriad and/or to the organism\u2019s right of the kinety with which they are associated; thus, polarity of the cell can be deduced (see Bipolar Kinety ) (Figs. 2.1, 2.2). Detritivorous : feeding on organic particles. Deuterostomisation : an evolutionary process in which oral kinetosomes are formed anew from somatic kinetosomes after the loss of the original oral ciliature; supposed to have occurred in lito- stomes and phyllopharyngeans . Diastole : see Contractile Vacuole . Dictyosome : see Golgi Apparatus . Dikinetid : a kinetid composed of two kinetosomes and their fibrillar associates; see Dyad , Monokinetid , and Polykinetid (Figs. 2.1E, 2.2c, 2.2d). Diploid : 2N number of chromosomes; character- istic of ciliate micronuclei whose chromosomes may be visible and enumerated at mitosis, although the true ploidy of many ciliates is unknown; see Haploid . Glossary 27 Diplokinety (pl. Diplokineties ): often, applied to a kinety with its kinetosomes doubled in some specific fashion; see Diplostichomonad . Diplostichomonad : type of double paroral whose infraciliature is composed of two parallel rows or files of kinetosomes \u2013 the inner or endoral membrane and the outer or paroral membrane ; the kinetosomes are never in dyads nor do they form a zigzag pattern, and all are ciliferous ; a type of diplokinety ; charac- teristic condition of clevelandellid armophoreans , many hypotrichs , and many stichotrichs . Director-meridian : argentophilic non-kinetosomal line on the midventral surface, coursing from the posterior margin of the buccal cavity to the cytoproct near the posterior end of the body; occasionally with non-ciliferous basal bodies near its anterior end, its locale is part of the site of formation of new buccal organelles during stomato- genesis ; characteristic of oligohymenophoreans , particularly scuticociliates ; a little-used synonym is bucco-anal stria (Fig. 2.4D; DM, Fig. 2.7i). Discoidal Vesicle : vesicle abundant in the phago- plasm and involved in building the food vacuole membrane. Dorsal Bristle : see Sensory Bristle . Dorsal Brush : see Brosse . Dorsal Zone of Membranelles : an older non- preferred term referring to tufts of syncilia , which are not membranelles , located anteriorly and dorsally on the bodies of many entodiniomorphids . Dyad : a paired set or couplet of kinetosomes in which the kinetosomal axes are at right angles (per- pendicular) to the axis of the line or file of the kinetal structure of which they are a part; in the case of many paroral structures, only the outermost kineto- some of the dyad is ciliferous ; the term is not used for the differently arranged pairs of kinetosomes comprising the circumoral ciliature , for which the preferred term is oral dikinetid (Fig. 2.1C). E Ectocommensal : see Commensal . Ectocyst : see Cyst . Ectoplasmic Flange : see Flange . Ectosymbiont ( of Ciliates ): microorganism, such as bacteria or other ciliates, attached to the outside of the host ciliate; common examples of ciliates as hosts include many psammophilic species (e.g., the karyorelictean Kentrophoros ) and commensalistic scuticociliates (e.g., Echinocyclidium ), and ses- siline peritrichs in which both bell and stalk may be involved (e.g., Zoothamnium niveum ). Edaphic : in a broad sense, pertaining to all kinds of soil, forest litter, and other types of terrestrial habitats, including mosses, lichens, and trunks and leaves of trees; synonym of terrestrial. Elineation : process by which a kinety \u201cdivides\u201d or separates longitudinally to produce a file of kineto- somes parallel to itself, increasing the number of kineties by one. Embryo : see Larval Form . Embryo Sac : see Brood Pouch . Enantiotropic : a kind of fission typical of oligo- trichous spirotrichs , said to involve a condition of inverse homothetogenic fission and shifting body axes via pronounced morphogenetic movements. Encystment : the process of cyst formation; see Cystation , Excystment . Endemic : regularly or only found in a cer- tain geographic region; see Cosmopolitan and Ubiquitous . Endocommensal : see Commensal . Endogemmy : see Budding and Endogenous Budding . Endocyst : see Cyst . Endogenous Budding : type of single or multiple fission taking place within a brood pouch , with the embryo or larval form(s) completely free of the parental form before emergence through the birth pore ; characteristic mode of reproduction of certain chonotrichs , where the process is called crypto- gemmy, and, especially, of certain suctorians (Fig. 2.11Ca, 2.11Cb). Endoplasmic Reticulum (ER) : system of internal membranes in the form of flattened cisternae, and/ or vesicles that are related to or derived from the Golgi apparatus ; surfaces of the ER membranes are sites of ribosomal activity involved in synthesis 28 2. Glossary of Terms and Concepts Useful in Ciliate Systematics of secretory proteins, which are then processed by the Golgi apparatus. Endoral Membrane : see Diplostichomonad , Paroral . Endoskeletal System : the term preferred by many students of the astome oligohymenophoreans (see Cytoskeleton ). Endosome : somewhat transient, brightly Feulgen- positive body in the paramere of the heteromerous macronucleus of cyrtophorine and chonotrich phyl- lopharyngeans ; the term is sometimes misused for the Feulgen-negative, RNA-containing nucleolus so commonly found, generally as numerous small bodies, in the nucleoplasm of the homomerous macronucleus and the orthomere of the heteromer- ous macronucleus