PLAN OF THE FLOWER. 65 
mint, while five-parted, the flowers have generally but four 
stamens; but on close observation we often find a small 
rudiment of the fifth stamen in its proper place, as if éts 
growth had been early stepped. And in Monarda and Catal- 
pa, only two stamens grow up to maturity, while three are 
mere rudiments (Fig. 202). Nevertheless, such flowers are 
said to be unsymmetrical. So the flowers of the Mustard 
tribe. The stamens are in two rows of four in each; but ot 
the outer row (or circle) two were checked in growth (or 
suppressed, as the botanists say) at the outset. (See Fig. 97.) 
The tendency to symmetry is manifest in all these cases. 
117. We must carefully distinguish between the terms 
unsymmetrical and irregular. The former refers to number 
only, the latter to form and size 
(Less. XIV.). The Mustard 
flower is unsymmetrical, but 
not irregnlar. The Orchis is 
irregular, but not unsymmet- 
rical. Snap-dragon is both 
irregular and unsymmetrical. 
Fig. 198. Nymphea odorata. 
Fig. 199. Petuls gradually passing into stamens. 
118. Here is a figure of the Water Lily (198), and a 
separate view of its sepals, petals, and stamens. Observe 
117. What difference between unsymmetrical and irregular? Examples. 
