26 BOTANICAL GAZETTE [JULY 
be produced by wounding. He interprets these reactions as a 
reversion to the ancestral condition as indicated by their occurrence 
in the fossil forms and in the primitive regions of living forms just 
mentioned. Ltoyp in a recent paper (43) has touched the same 
subject and given his approval to the general conclusion as stated 
by THomson. The latter calls attention to the fact that the coni- 
fers which do not have spur shoots show no evidences, either in their 
primitive regions or as the result of wounding, that they have 
descended from ancestors possessing spur shoots. 
STANFORD UNIVERSITY, CALIFORNIA 
