THE CRYPTOGAMIA OR FLOWERLESS PLANTS. 



127 



525 



Hepatic*. 523, Marchantia, sterile plant. 524—5, Fertile plant. 52G, Vertical section of 

 the fertil-receptacle ; 527, of a perianth, showing the sporange bursting. 528, One of the elators 

 with four spores. 529, Portion of it highly magnified. 



543 544 



of the flowering plants. In the mosses, liver- 

 worts, etc., they appear only on the fall-grown 

 plant ; in the ferns, Equisetacese, etc., they ap- 

 pear only on the prothallus, the earliest growth 

 of the spore, and here the archegone gives birth 

 to an embryo, whence at length the true fern 

 arises, while the prothallus dies away. 



630. Spores. These 

 are the true reproductive 

 germinating bodies of the 

 Cryptogams. They con- 

 sist each of a single cell, 

 often exceedingly minute, 

 and produced in immense 

 numbers. The cell wall 

 of the spore may be sim- 

 ple (Botrytis) or double, 

 as if a cell within a cell 

 (ferns). But the spores „ .'*„,, ,, T , 



* ' i Fungi. 53", Agancus (Mushroom) in various stases: e, 



are often apparently tearing open the volva; &, annul as, the remains of the veil 

 double or 2-celled Clich- ^' c ' P ileus; "' n >y ci -' liuin - 538. Portion of the gills. 539, 

 . 11 i Basiilia and spores from the same (main. 410 diarn.)- 540, 



ens), Or 4-Celled, or 6, 8, Cyathus; 541. Section. 542, One of the conceptacles. 543, 

 Or many-celled. These P enicililim (mildew). 544, Mucor; a, mycelium. 



compound spores are in fact spore-vessels inclosing several spores yet 

 immature, and called sporidia or theca-spores. The spores or sporidia 

 are often inclosed in still larger cells called the sac. 



631. Endospores and exospores. Spores are developed either in 

 tho interior of the parent cell or on the outside of it, and hence the di- 



