this paper, it may be stated here by way of a generali- 
zation that: (1) The anaerobic degradation of the plant 
cell wall in sediments involves fundamentally similar struc- 
tural changes in all plant tissues; and (2) These degrada- 
tive changes are directly related to basic physical, chemical 
and structural features of the cell wall. 
The significant features in the general pattern of struc- 
tural change in the anaerobic degradation of wood were 
described in a previous study of numerous woods recov- 
ered from an archeological site in Boston, Massachusetts 
(Bailey and Barghoorn, 1942). Since the publication of 
this earlier study, a far wider range of material from 
various geological horizons has been examined anatomi- 
cally and, in part, microchemically. A more detailed de- 
scription of these studies is in the course of publication 
(Barghoorn 1949),' but it seems desirable to review here 
the salient features of these investigations and their re- 
lation to various paleobotanical and anatomical problems 
as well as their possible bearing on dating archeological 
remains. 
In wood of varying age, entombed in mineral or or- 
ganic sediments, and permanently submerged, there oc- 
curs a gradual reduction of the amount of cellulose con- 
tained in the original unmodified cell walls. Depending 
on the availability of oxygen during degradative changes, 
and its effect on microbiological activity, a variable de- 
gree of ‘‘humification’’ results. Stumps of trees, sub- 
merged by sudden inundation, commonly occur embed- 
ded in peat deposits, yet may show little evidence of the 
‘‘humification’’ so characteristic of the peat. For exam- 
ple, in the fresh water peats and ‘‘buried forests”’’ of the 
‘As a section of the second monograph on the archeology, geology, 
stratigraphy and paleobotany of the Boylston Street Fishweir (Papers 
of the Robert S. Peabody Foundation for Archeology). 
[ 4] 
