A LIVERWORT. 



Riccia. 



BRYOPHYTES; HEPATIC^; RICCIALES. 



PRELIMINARY. 



THIS plant is found growing upon earth, stones, etc., 

 in very damp places, one species, R. fluitans, being a 

 distinctly aquatic form. The plants may be recognized 

 by their thick, dark-green, dichotomously branching small 

 bodies, which are sometimes discoid with numerous rhi- 

 zoids on the lower side. If Riccia cannot be obtained, 

 the common Ricciocarpus natans will answer for this 

 study, though some structures are less easily made out in 

 it than in Riccia. In addition to the actively growing 

 plant bodies, care should be taken to obtain specimens 

 in which the dark globular sporophytes (capsules im- 

 bedded in the dorsal tissues) can be seen. Material in 

 which very young sporophyte capsules can be distin- 

 guished is likely to contain a few of the sexual organs. 



LABORATORY WORK. 

 GROSS STRUCTURE. 

 With a good specimen in hand, observe: 

 i. The general form of the plant. 

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