181 
FOSSIL WOOD FROM THE PETRIFIED FOREST OF 
ARIZONA 
The Museum has recently acquired, through the kindness of 
Mrs. John J. Kane, two fine specimens of fossil wood, from the 
so-called ‘‘Petrified Forest,’’ near Adamana, Arizona. The 
specimens consist of complete cross sections of a tree trunk about 
thirteen inches in diameter, one of which is polished so that the 
mineralization and what remains of the original structural 
characters of the wood are clearly shown. The region which 
includes the most interesting pees of the forest is embraced 
in the Petrified Forest National Monument, a reservation created 
forty and one half square miles. Under the conditions which 
now obtain specimens of the fossil wood may not be taken away 
by collectors as was formerly freely done, and the Garden is, 
therefore, to be congratulated on having secured these two 
specimens, especially the polished one, which was sent to England 
by Tiffany and Com agree in order that the work of polishing 
could be satisfactorily don 
The particular form of ‘fonilization exemplified in the wood 
from this region is what is known as silification, or the replacement 
of the woody tissue by silica in one or more of its various forms, 
chalcedony, jasper, quartz crystals, etc. Of course every in- 
aie person now knows that fossil wood of all kinds represents 
s formerly the wood of living trees; but it may be in- 
eee to note that this fact was a subject of controversy and 
discussion until the beginning of the last century, and that all 
of the older writers on natural history who had occasion to study 
such material had either very vague or entirely erroneous ideas 
in regard to its true nature and origin. In Gerard’s ‘‘ Herbal,” 
published in 1597, for example, may be found these words in 
connection with his discussion of a fossil tree stump: ‘Among 
the wonders of England this is one of great admiration, and 
contrary unto man’s reason and capacitie, that there should bee 
a kinde of Wood alterable into the hardnesse of a stone called 
