ITS NORMAL STRUCTURE. 31 
theory of the ‘ transformation of the leaves into the floral organs,’ * to which allu- 
sion has already been made (§ 25). When the bud is developed into a branch, 
instead of a flower, the leaves are usually arranged in a simple spiral line. This 
spire may be broken up into equal circles or whorls, from causes to be hereafter 
explained. In either case the leaves of one spire, or circle, do not issue from the 
stem at points exactly over the Jeaves of the next circle below, but over the iter- 
vals between them. 
62. This simple normal structure of the flower is, however, subject to many 
apparent exceptions, so that few, comparatively, are found perfectly conformable 
to it. Of these few the order Linacex affords good examples. In the flax 
(Lihum) the flower is built upon the normal plan, consisting of 5 sepals, 5 petals, 
5 stamens, and 5 pistils (each with 5 double carpels), all alternating with each 
other, according to the diagram (Fig. 5;1). 
2 3 
FIG. 5.— Plan of flowers; 1, ova regular and symmetrical flower, as the flax (Linum); 2, 
of the cherry, showing the four whorls of stamens ; 3, of the primrose, showing the position 
of the suppressed row of stamens; 4, of the Samolus, showing the position of the 5 abortive 
stamens ; 5, of a labiate flower, as the hemp-nettle (Galeopsis), where one stamen and one 
carpel is wanting; 6, of a cruciform flower, as mustard, where the stamens are in two” 
whorls, two of those in the outer whorl and two carpels being suppressed. 
; 
‘63. If, with this adopted standard, we compare the numerous 
* This theory was first suggested by Linnzus, the founder of Systematic Botany, and sub- 
sequently by Wolff and Goethe. After having been long unheeded by botanists, it has at 
length been revived by modern writers of the highest merit, and shown to be perfectly coin- 
cident with facts. ‘The adoption of this theory, accordingly, has given a new aspect to 
botany, and rendered it one of the most philosophical and inductive of the natural sciences.’ 
See Gray’s Bot. Text-Book, Chap VIII, where this theory is clearly stated, and richly illus- 
trated. 
