A PICE A FROM THE GLACIAL DRIFT. 
WILBUR A. THOMAS. 
Early this year (1917) we received at our laboratory a piece of 
fossil wood from Mr. B. 0. Walden of Wallingford, Iowa. Wall- 
ingford is in the northern part of the state, about thirty miles 
southeast of Spirit Lake. Mr. Wolden secured this wood from 
a farmer near Wallingford. It was taken up with an eighteen 
inch auger drilling machine from a depth of eighty feet. Along 
with this wood, were found some well preserved bits of moss, 
some leaves or needles which resembled spruce needles, and a 
very small, immature cone. 
The glacial drift which held this material is estimated to be 
at least 10,000 years old. In general appearance the wood is 
coated with claylike soil, and is light, much as old drift wood. 
It is in an excellent state of preservation. Under the microscope 
it may be noticed that the large cells at the beginning of the 
annual growth are in some cases broken in, or caved in, as though 
from pressure of the earth. 
The following things may be seen in the sections. There are 
no tertiary spiral markings on the trachejds. The resin canals, 
pitting, and bars of Sanio prove it to be Abietinean ; the normal 
resin canals put it in the Pineae. It is differentiated from 
Pinus by the thick walled secretory cells. 
The tangential pitting is well marked, the rays are thick 
walled and Abietinean ; the marginal trachieds are smooth walled, 
and in some cases there are masses of carbon in the pits. 
According to Mr. Torrey of Harvard University, the intergla- 
cial wood is a Piceoxylon. It cannot be a Pseudotsuga for there 
is no evidence of spiral markings. Neither can it be a Larix 
for there is no dark colored heart wood. It can safely be 
placed as a Picea. The very interesting fact may be noted here 
that the White Spruce, or Picea alba, is not found growing in 
Iowa, nor closer than the Black Hills of Dakota. The range 
of the Picea alba is Newfoundland, Nova Scotia, and New Bruns- 
wick, westward through Quebec and Ontario to the forest limit 
of Manitoba. In the prairie region it is found in the sand hills 
bordering the first prairie steppe. Occasionally it is found in 
