394 SEMI-CENTENNIAL OF TORREY’ BOTANICAL CLUB 
As a rule chicory plants are much branched. Grown from seed 
there is in the first year a single main stem. In the variety “‘red- 
leaved Treviso" there is a rather uniform duplication of the single 
main stem, giving two stem elements usually quite pronounced 
but cohering strongly. 
From the main axis numerous laterals arise which are further 
branched, producing bushy plants as shown in PLATES IO and 
II. All branches end in flower heads, but considerable variation 
exists in the development of the ultimate branches, not only for 
different individual plants but among the different branches of a 
single plant. In some plants many of the ultimate branches are 
elongated, giving a divaricate habit with many heads that appear 
solitary and decidedly terminal (PLATE 12, marked 1). Branches 
which are lateral to these are usually less elongated (PLATE 
12, 2 on plate), so that the flower heads appear sessile, but 
these [шї turn’ may have further lateral but much reduced 
branches. Very often several branches constituting a system in 
the axil of a leaf are all much reduced so that several heads appear 
much branched and closely compacted, as shown at points indi- 
cated as 3 оп PLATE 12. In some plants the ultimate branches 
are well developed and the clusters contain few heads involv- 
ing only the last few ranks of ultimate branches. Such rather 
simple grouping is shown in PLATE I 3, A, in the series of laterals, 
all from the same plant, which show a graded transition from a 
lateral with a terminal and three sessile laterals (1); to two 
laterals (3); to one lateral (4, 5, 6, and 7); the series illustrating 
successive stages of shortening of branches. B of the same plate 
has a somewhat more marked development of secondary laterals. 
In other cases there is little development of penultimate branches, 
so that clusters of numerous heads are frequent and the general 
branching is more sparse. The branches shown in the plate are 
near the apex of the main or large basal laterals; the larger main 
laterals near the base of a plant have larger laterals near their 
bases, which in turn duplicate the branching system of the more 
terminal parts of the main branches. 
As all flower heads are in reality terminal for the particular 
branches, the distinction of terminal and lateral heads is purely 
a relative one. A terminal head blooms before a head that is 
