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SUMMARY. 
table fossils of the coal measures is extracted 
from the able outliue of our science published 
by Monsieur Adolphe Brongniart in 1828."^ 
Subsequent researches have added to the 
lists and have made the important alteration 
of placing some dicotyledonous species of 
timber trees within the ranks of the coal 
plants. Brongniart adds, A .glance at this 
table will suffice to shew the difference 
which exists between the vegetation of the 
era referred to and that which now^ covers 
the globe. The greatest part of this flora is 
formed of vascular cryptogamia, that is to 
say Ferns and their allied families, which 
constitute by themselves five sixths of the 
sum total of the plants of this period, 
whilst they form but one thirtieth of actual 
vegetation ; on the contrary dicotyledonous 
plants, which compose more than three 
fifths of living vegetables, probably did not 
exist at all at this epoch, or formed but one 
twelfth of its vegetation, supposing that we 
place in this class the twenty species the 
place of which is uncertain.” 
* Prodrome cViine histoire des Vegetaux Fossilesr 
