Glossary. 



Aethalium : A compound fructification formed by the union of many 



sporangia ; the walls of the inner sporangia are more or less 



imperfectly developed. 

 Capillitium : A system of simple or branched, solid or tubular threads, 



developed within the sporangium, and usually assisting in the 



dispersion of spores. 

 Cartilaginous : A term applied to a stout, uniformly thickened 



membrane. 

 Columella : A supporting structure arising from the base of tho 



sporangium and giving attachment to the capillitium ; it may be 



either convex, conical, clavate or cylindrical ; in stalked sporangia 



it is directly continuous with the stalk. 

 Cortex : An outer covering investing the aethalium. 

 Cytoplasm : The finely granular and hyaline portion of protoplasm. 

 Effused : Flattened and irregularly extended. 

 Elaters : Free tubular capillitium-threads marked with spiral bands, 



characteristic of the genera Trichia and Oligonema. 

 Epispore : The outer layer of the spore-wall. 

 Fusiform : Spindle-shaped. 



Flagellum : The whip-like organ of motion of a swarm-cell. 

 Hyaline : Glassy clear. 



Hyaloplasm : That part of the cytoplasm which is free from granules. 

 Hypothallus : A membrane or system of strands from which the 



sporangia arise. 

 Laciniate : Jagged or torn. 

 Lime-knots : Expansions in the threads of the capillitium containing 



granules of calcium-carbonate. 

 Macrocyst : The resting condition of a very young plasmodium, 



consisting of a mass of cytoplasm with nuclei, enclosed in a 



double wall. 

 Microcyst : The resting condition of a swarm-cell, consisting of a 



small spherical mass of cytoplasm and a nucleus, enclosed by a 



hyaline wall. 

 Muricate : Rough, with hooked spines. 

 Nodes : In the genus Cribraria, the upper half at least of the sporangium 



wall persists as a network of slender threads, usually conspicuously 



enlarged or thickened at the points of junction or nodes. 

 Plasmodiocarp : Sessile sporangia having a vein-like or irregular 



outline. 

 Plasmodic Granules : Minute, strongly refracting, usually coloured 



granules, conspicuous in the walls of sporangia of the genera 



Lindbladia, Cribraria, and Dictydium ; they dissolve in acid, and are 



well preserved in Canada balsam. 

 Plasmodium : A mass of naked protoplasm formed by the union of 



swarm-cells, and exhibiting a rhythmic circulation. 



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