OTHER CRYPTOGAMS IN CULTIVATION, 151 



considered by botanists as analogous to the sili- 

 cious particles in the stem of Equisetum. The 

 Ckaras and Nitellas may be kept a long time in 

 water with a little earth at the bottom, and are 

 very interesting. Their large cells, under the 

 microscope, are excellent objects to illustrate the 

 rotation or circulation of the protoplasm. Charas 

 are reproduced in two ways, by an oosphere after 

 fertilization, or by bulblets analogous to the buds 

 of other plants. Charles Johnson, Esq., in " Ferns 

 of Great Britain," London, 1859 (almost the only 

 English work illustrating the common species of 

 Cham and Nitella), says, " Young plants may be 

 easily raised of all the species." He had grown 

 many, especially C. aspera, himself. Later works 

 than this, however, should be consulted for the 

 structure and development of these plants. 



Among the Hepaticce the Marchantia is very 

 interesting in cultivation ; and on the trunks of 

 trees, and creeping over rocks, will be found many 

 species of Frullania, Jungermannia, Madotheca, 

 Ptilidium, &c., many of them in appearance re- 

 sembling the Lichens, for which they are often 

 mistaken by young botanists. Of course these 

 plants only come into our collection as accessories 

 to the ferns ; but they will repay our attention and 

 care. 



Of the growth and development of the Mosses 

 much might be said. In the out-door fernery they 



