Centripetal: developing from without inward, or from exterior to interior. 



Centrosome, Centriole: a small body, usually lying just outside the nucleus; in 

 flagellates a granule functioning in the neuromotor system. 



Cespitose: See caespitose. 



Chitin: a hard substance, C15 H26 Oio N2, found in skeletons of lower animals 

 and in cell walls of some algae. 



Chloroplast: a body (plastid) in the cell containing chlorophyll as the pre- 

 dominating pigment. 



Chlorococcine tendency: evolutionary trend toward the Chlorococcales in the 

 green algae (or in other groups) from a solitary motile cell which has 

 ability to reproduce vegetatively by cell division to a nonmotile type of 

 cell (uninucleate or coenocytic) in which vegetative cell division is not 

 used. 



Chromatophore: a colored body in a cell which has a pigment other than 

 chlorophyll predominating. 



Chromatic: colored. 



Chromatin: the material in the nucleus which takes up dyes readily; nuclear 

 material composing chromosomes. 



Chromoplasm: the portion or part of cell content containing pigments, not in- 

 volving plastids; in Myxophyceae the cytoplasm just widiin the cell wall 

 and exterior to the "central body." 



Chromulinad: a type of cell similar to Chromulina which has one flagellima. 



Chroococcoidal: in shape or arrangement similar to Chroococcus; cluster of 

 round cells. 



Chrijsochrome: brown pigment found in Chrysophyceae. 



Cilium (pi., Cilia): fine, hair-like extensions, usually from the outer membrane 

 of a cell; used in locomotion by ciliated protozoa; fibrils on the flagella of 

 the Heterokontae. 



Cingulum: band within the diatom cell which holds the two overlapping sec- 

 tions of the wall together. 



Circinate: coiled, rolled; twisted. 



Cirque: arranged in a circle or nearly so. 



Citriform: lemon-shaped. 



Clathrate: with openings; intermittent spaces. 



Clavate, Claviform: wedge-shaped. 



Coalesced, Coalescent: joined, united; grown together. 



Coccoid: round; spherical; cells as in Chroococcus, Aphanocapsa. 



Coenohe, Coenohium: a colony of cells arranged to form a hollow sphere. 



Coenocytic: with many nuclei; a thallus constructed of multinucleate cells; 

 a thallus in which there are no cross walls. 



Collar: narrow neck around the flagellum-opening in a shell or lorica; some- 

 times a sheath at the base of a bristle or hair. 



Colligate: united, joined, as in some species of Spirogyra which have an exter- 

 nal collar-like piece about the cells at the cross walls. 



Colony: a group of individuals, joined together or merely inclosed by a com- 

 mon sheath or investing material; a group of cells joined together to form 

 a filament (rarely used in this sense); a cluster of individual plants, 

 closely associated in growth. 



Commensal: referring to two or more species living in close association and 

 deriving mutual benefits. 



Complanate: level, smooth, even, plane. 



Concentric: layers or structures with a common center. 



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