THE FLAVONES OF RHUS 
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Perkins conclusion that the same flavone is not Hkely to be found in 
both the wood and leaves of the same species. Fisetin is distinctively 
a wood flavone, and would appear to be an end product of metabolism. 
It is now known from Rhus Cotinus, R. rhodanthema, R. typhina, and 
R. glabra. The first two do not belong to Rhus in the restricted 
sense, but to the genera Cotinus and Rhodosphaera, respectively. 
Our studies are therefore the first to demonstrate the presence of 
fisetin in wood of species belonging to Rhus proper (the true sumachs). 
The distinctive leaf flavone of Rhus proper is myricetin. It has 
been known from R. Coriaria, and we are able to add R. glabra and R. 
copallina. It is probably a plastic substance. Although we have 
thus far been unable to trace its relationship to the fisetin of the stem, 
or to the anthocyanins of the leaf and berries, efforts along this line 
will not be abandoned. The flavones are becoming increasingly inter- 
esting to the physiologist and geneticist, and on this account we 
venture to present this slight addition to our knowledge of their 
distribution in plants. 
