1911] CHAMBERLAIN—CYCAD TRUNK oI 
As soon as a cone begins to develop, a new meristem appears 
very close to the peduncle, and this new meristem may form succes- 
sive crowns of leaves, but sooner or later it becomes transformed 
into a cone, which is really only a highly modified crown of leaves 
Fic. 4.—Dioon spinulosum: longitudinal section near the top of the piece shown 
in fig. 1; note 5 cone domes and, at the tip, a part of another; three ribs and parts 
of two more are shown; between the ribs are scale leaves; X}. 
terminating the growth of its axis. The process is then repeated. 
An instructive view of this phase is seen in fig. 6. A little to the 
right of the center is the peduncle of a large ovulate cone, and at its 
left is the new growing point which has produced a crown of foliage 
