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distinguished by longer coronal ciliature from a posteriorly adjacent neck; also used for the border membrane of mobiline peritrichs . Coronal Ciliature : term used in different ways, but most commonly referring to the circlet of relatively long cilia at the ends of somatic kineties or isolated from them and surrounding the apical cytostomal area, the corona , of various haptorians and located anterior to the neck region of the body. Cortex (pl. Cortices ): in the broadest sense, the outer portion or \u201clayer\u201d of the ciliate body, sometimes termed the cell envelope; includes the pellicle and the infraciliature sensu lato and bears the cilia ; its various openings, pellicular ridges , alveoli , cilifer- ous kinetosomes , and their fibrous and microtubular associates comprise the corticotype ; mitochondria are in the cortex of many ciliates. Cortical Vesicle : see Alveolus, Pellicular . Corticotype : specific pattern of cortical structures or organelles found to be characteristic of a given organism or population of organisms within a species; cortical pattern especially as made visible follow- ing application of silver-impregnation techniques (Figs. 2.3, 2.4). Cosmopolitan : capable of population growth in many different places worldwide. Crista (pl. Cristae ): see mention under Mito- chondrion . Crochet : see Attachment Organelle . Crypt : see Brood Pouch ; but this is the preferred term for use with chonotrichs ; also occasionally employed in a more general sense for any cleft or depression in the body or elsewhere (Crp, Fig. 2.11Ca). Cryptogemmy : see Budding and Endogenous Budding . Cryptotelokinetal : telokinetal stomatogenesis in which the oral anlage originates as subequa- torial kineto fragments derived from non-ciliated kinetosomes residing in subcortical pouches; found in entodiniomorphid trichostomes . Crystallocyst : minute body, quite numerous in the cortex of the scuticociliate Conchophthirus ; pos- sibly a kind of extrusome . Cursorial : adapted to or specialized for \u201crunning\u201d; true of some hypotrich and stichotrich cirri . Cuticular Pore : see Pellicular Pore . Cyrtocyst : a short, curved extrusome found sub- pellicularly in the haptorian Didinium . Cyrtos : tubular cytopharyngeal apparatus , often curved, the walls of which are strengthened by lon- gitudinally arranged nematodesmata derived from circumoral kinetosomes and lined with extensions Glossary 25 of postciliary microtubules ; the nematodesmata may be interconnected and/or wrapped circumferentially by annular sheaths of diffuse fibrous material and an amorphous dense substance that may form capitula proximally; contains no toxicysts; septa and spe- cialized phagoplasm may be present; typical of members of the Classes PHYLLOPHARYNGEA and NASSOPHOREA , including especially the \u201c cyrto- phorine gymnostomes \u201d of older classifications; principal synonyms include nasse and pharyngeal basket; of Greek derivation, the word literally means \u201ccurved\u201d but also may be extended to imply \u201cbasket\u201d or \u201ccage\u201d, all three descriptively appropriate to its usage here; the cyrtos is to be compared with the rhabdos , the other major type of cytopharyn geal apparatus characteristic of litostome ciliates, alleg- edly less complex, non-curved, often containing toxicysts, and lined with transverse and bulge micro- tubules (Figs. 2.5D, 2.7j). Cyst : non-motile inactive stage in the life cycle of many ciliates, generally thought to serve the roles of protection and dispersal; when considered a protective stage, organism typically rounded up, mouthless, and surrounded by three or more secreted layers or \u201cmembranes\u201d (i.e. pericyst, ecto- cyst, mesocyst, endocyst, metacyst); sculptured on the outside, and with or without an emergence pore, which may have an operculum ; several types have been described, indicating the diverse functions of cysts \u2013 (1) digestive, (2) division, multiplica- tive, propagative or reproductive, (3) infective, (4) invasion (cuticular), (5) phoretic, (6) protective, (7) reorganization or reconstructive, (8) resting, and (9) temporary (Fig. 2.9A). Cystation : processes involved in formation of and departure from a cyst . Cystic Membrane : see Cyst . Cyst Wall : see Cyst . Cytobrain : see Neuromotorium . Cytogamy : autogamy in pairs; non-preferred term. Cytokinesis : strictly applied meaning division of the cytoplasm; often used in a general sense as a synonym of cell division (see Fission ). Cytopharyngeal Apparatus (pl. Apparati ): the complex of microtubular and microfilamentous components that support the cytopharynx ; most conspicuously developed in ciliates that have the cyrtos or the rhabdos ; see Cytopharynx . Cytopharyngeal Armature : refers to the nemato- desmal elements of a cytopharynx , especially of the cyrtos . Cytopharyngeal Basket : see Cyrtos and Rhabdos . Cytopharyngeal Pouch : reservoir-like enlarge- ment or receiving vacuole of the cytopharynx of a few ciliates (e.g. the carnivorous macrostome stage of Tetrahymena vorax ); when food-filled, it pinches off as a regular membrane-bound food vacuole . Cytopharyngeal Rod : synonym for a nema- todesma that supports the cytopharynx ; see Cyrtos and Rhabdos . Cytopharynx (pl. Cytopharynges ): non-ciliated tubular passageway of varying length in different ciliates, leading from the cytostome proper into the inner cytoplasm of the organism; typically, food vacuoles are formed at its inner or distal end, when it retains its own integrity during the feeding proc- ess; when its walls are particularly strengthened, the cytopharyngeal apparatus may be known by such specialized names as cyrtos or rhabdos (Cph, Figs. 2.5Ca, 2.6Ac). Cytoproct ( Cyp ): cell anus; when present, gener- ally permanent, slit-like opening in the pellicle , near the posterior end of the body, through which egesta may be discharged; its edges, resembling a kind of pelli cular ridge and reinforced with micro- tubules, are argentophilic ; in some species, the Cyp is a cortical landmark of taxonomic signifi- cance, located in or just to the left of the posterior portion of kinety number 1 (Cyp, Figs. 2.3Ai, 2.4K, 2.7f, 2.7i, 2.11Aa). Cytopyge : a non-preferred term; see Cytoproct . Cytoskeleton : the complex of microtubular and microfilamentous components in the cytoplasm that provide structure and form to the cell body; generalized term referring to any secreted inor- ganic or proteinaceous material within or below or on the surface of a ciliate, covering or involving all or some specific part of the body and lending considerable rigidity to the shape of the organism; see Skeletogenous Structure , a term with which it is broadly synonymous, although the emphasis in meaning may vary in usage by different workers. 26 2. Glossary of Terms and Concepts Useful in Ciliate Systematics Cytospindle : sets of longitudinally-oriented cortical microtubular ribbons that appear transiently during cytokinesis of some nassophoreans and peniculines . Cytostome : literally \u201ccell mouth\u201d; the \u201ctrue\u201d mouth or oral opening; simply a two-dimensional aperture through which food materials pass into the endo- plasm of the organism via a more or less distinct cytopharynx ; may open directly to the exterior or be sunken into a depression or oral cavity of some kind, such as an atrium , vestibulum , or buccal cavity ; often definable as the level at which pellicular alveolar sacs are no longer present, it may occur as an angled or tipped elliptical opening with a long axis of consider- able length (Cs, Figs. 2.5Ca, 2.6Aa). Cytostome-cytopharyngeal Complex : convenient generalized term to refer to the inseparable comple- ment of the cytostome and the adjacent and really continuous cytopharynx . Cytotaxis : broad concept that considers the