Glossary 



Terms Relating to Fresh-water Algae 



Abscission: separation of a branch or portion of a thallus by degeneration of 



cells at its base, or by constriction. 

 Achromatic: without color. 



Achromatin: the material of the nucleus exclusive of the chromatin. 

 Acicular: needle-shaped. 



Adnate: joined along a relatively broad surface. 

 Aerobic: using free oxygen in respiration. 

 Agglutinate, Agglutinated: sticking together; adherent, as with mucilaginous 



sheaths. 

 Akinete: a spore produced from a vegetative cell which has developed a thick 



wall about a concentrated food reserve. 

 Akontae (Akontean): plants in which neither vegetative cells nor reproductive 



cells have flagella. 

 Alveolar: with cavities or pits. 



Amoeboid: like an amoeba in locomotion or in nutrition; creeping by pseudo- 

 podia. 

 Amorphous: without definite shape. 



Anabaenin: a pigment found in the blue-green algal genus Anahaena. 

 Anaerobic: carrying on respiration without the use of free oxygen. 

 Anastomose: referring to sheaths, filaments, or thaUi which intermittently join 



and separate; sometimes joining in such a way as to form a network. 

 Androsporange, Androsporangium: box-like cell which produces a special spore, 



androspore, which develops into a dwarf male plant ( Oedogoniaceae ) . 

 Androspore: a spore which gives rise to an epiphytic dwarf male plant (Oedo- 



goniales ) . 

 Aniso gametes: sex cells of a plant shghtly dissimilar in size, shape, or behavior. 

 Alternation of generations: a life cycle in which both asexual and sexual plants 



occur, one giving rise to the other by the production of spores, and by the 



fusion of gametes. 

 Annular: ring-like. 



Antapical: posterior; basal; opposite the apex. 



Antapical plates: sections of the cell wall of Dinoflagellatae at the posterior pole. 

 Antheridium: a male gametangium or sex organ. 

 Antherozoid: a male gamete; sperm, or spermatozoid. 

 Apex (Apical): forward tip; anterior end. 



Apical plates: sections of the cell wall of Dinoflagellatae at the anterior pole. 

 Apiculate: abruptly tapered to a fine point. 

 Aplano gametes: non-flagellated gametes. 

 Aplanospore: non-motile asexual spores, formed one to several in but not the 



same shape as a parent cell. 

 Aplanosporangium: cell which gives rise to aplanospores. 

 Apposed: paired; opposite in definite relation to one another. 

 Appressed: pressed together; closely adjoined. 

 Arborescent, Arbuscular: branched in tree-like fashion; bushy. 

 Arachnoid: like a web. 



[596] 



