CHAPTER XIX 
BRYOPHYTES 
The Bryophytes, comprising the two groups of Liverworts 
(.Hepaticae ) and Mosses (Musci), present a great diversity of struc¬ 
ture, some being so delicate that good preparations are very uncer¬ 
tain, while others are so hard that it is difficult to get satisfactory 
sections. Between these extremes, however, there are many forms 
which readily yield beautiful and instructive preparations. 
If but one fixing agent should be suggested for the entire group, 
it would be chromo-acetic acid with 1 g. chromic acid and 2 c.c. 
acetic acid to 100 c.c. of water. It should be allowed to act for at least 
24 hours. For morphological study, Dr. Land uses a formalin 
alcohol solution (6 c.c. commercial formalin to 100 c.c. of 50 per cent 
alcohol), which he has tested in extensive collections in various 
tropical regions, where it has been impracticable to use the chromic 
series, with its tedious washing and changing of alcohols. Material 
may be left in the formalin alcohol solution until needed for use, a 
convenience which will hardly be appreciated by those who are 
always within reach of a laboratory. 
For general study, the small, delicate forms may be mounted 
whole in Venetian turpentine. 
Instead of treating forms in a taxonomic sequence, we shall 
consider first the gametophyte structures under the headings thallus, 
antheridia, and archegonia, and shall then turn our attention to the 
sporophyte. 
HEPATICAE 
Some of the liverworts are floating aquatics, but most of them 
grow on logs or rocks or upon damp ground. They are found at their 
best in damp, shady places. Many of them may be kept indefinitely 
in the greenhouse. Riccia, Marchantia, Conocephalus, Asterella, and 
many others vegetate luxuriously, and often fruit if kept on moist 
soil in a shady part of the greenhouse, and they do fairly well in the 
ordinary laboratory if covered with glass and protected from too 
intense light. Riccia natans is a valuable type for illustrative 
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