The seeds of the cryptogams or flowerless plants are not true seeds and are properly designated "spores" (see Fruit).
The apparently clear distinction between flowering and flowerless plants has been broken down by the series of gradations between the two exhibited by the Lycopodiaceae, Rhizocarpeae, and Gymnospermeae.
The plant world falls into two great divisions, the higher or flowering plants (Phanerogams), characterized by the formation of a seed, and the lower or flowerless plants (Cryptogams), in which no seed is formed but the plants are disseminated by means of unicellular bodies termed spores.
Each class of flowerless or cryptogamic plants requires special treatment for the herbarium.
Flowerless group of ferns begins to shrink in size, and no longer
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