SIGILLARIA. 
G7 
were once and repeatedly common forms in 
our land. 
We may here too describe the Sigillaria, 
that companion of the Calamite and Lepi- 
dodendron^ whose place is still uncertain in 
systems constructed on the basis of present 
phenomena. This was another monarch of 
the woods, marked with deep furrows and 
round scars. It is said to resemble a lofty 
cactus, or Zamia, with wide-spreading roots, 
the latter from their external ornaments, 
long considered to be a separate plant and 
called Stigmaria. 
Fossil remains of these trees are exceed¬ 
ingly numerous, and in very many instances 
they are discovered vertical to the floor of 
the strata in which they occur. 
There are upwards of fifty species, all 
with deeply fluted dotted stems. Their 
colossal forms, scantily crowned with fern¬ 
like leaves, have largely ministered in the 
formation of coal. The trunk, once hollow 
or filled with succulent matter, is now a 
pillar of sandstone, having apparently been 
broken off and filled from above. 
