PAST HISTORIES OF PLANT FAMILIES 163 



We must now bring forward the more important of 

 the facts known about the fossils of the various groups 

 of lower plants. 



BRYOPHYTES. Mosses. Of this family there are no 

 specimens of any age which are so preserved as to show 

 their microscopical structure. Of impressions there are 

 a few from various beds which show r , with more or less 

 uncertainty in most cases, stems and leaves of what 

 appear to be mosses similar to those now extant, but 

 they nearly all lack the fructifications which would deter- 

 mine them with certainty. These impressions go by 

 the name of Muscites, which is a dignified cloak for 

 ignorance in most cases. The few which are quite satis- 

 factory as impressions belong to comparatively recent 

 rocks. 



Liverworts are similarly scanty, and there is nothing 

 among them which could throw any light on the living 

 forms or their evolution. The more common are of the 

 same types as the recent ones, and are called Mar- 

 chantites, specimens of which have been found in beds 

 of various ages, chiefly, however, in the more recent 

 periods of the earth's history. 



It is of interest to note that among all the delicate 

 tissue which is so well preserved in the "coal balls" and 

 other palaeozoic petrifactions, there are no specimens 

 which give evidence of the existence of mosses at that 

 time. It is not unlikely that they may have evolved 

 more recently than the other groups of the " lower " 

 plants. 



CHARACE^. Members of this somewhat isolated 

 family (Stoneworts) are better known, as they fre- 

 quently occur as fossil casts. This is probably due to 

 their character, for even while alive they tend to cover 

 their delicate stems and leaves, and even fruits, with a 

 limy incrustation. This assists fossilization to some 

 degree, and fossil Charas are not uncommon. Usually 

 they are from the recently deposited rocks, and the 



