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of commerce. No female hand, in copying the most beautiful 
design of lace-work, could produce more exquisite elegance ot 
structure than is apparent under the microscope, arising from 
Section of the stem of an elm, # from which plates of hark have been raised 
all round the tree, some from above downwards as at a , others in 
the contrary direction as at b. These strips of bark have remained 
adhering by one of their extremities either to the bark above A, or to 
the lower bark E'. At g the strips of bark have been removed m order 
to show better what has taken place during the experiment, brom the 
upper surface of the wound have arisen numerous adventitious roots r. 
The strips of bark a and b have given rise to plates of bark, which attain 
one centimetre in thickness. They are clothed with new bark ; the 
surface of the denuded wood has also produced thick layers of wood and 
of bark c. At the surface of the new productions l, plates ot bark or 
of denuded wood have arisen from tubercles bearing each seven or eight 
adventitious buds. 
# Tr4cul, Annales des Sciences Naturelles Bot., t. xx. pi. 8. 
