1883. ] Development of a Dandelion Flower. 1213 
the original obconical mass, that they are all essentially hypog- 
ynous, and that their separate appearance at the so-called node 
is simply a freeing of their upper extremities. In this case the 
real order of development remains acropetal, and the apparent 
late appearance of the calyx due only to the late development of 
its upper portions. 
Simultaneously with this constriction two other changes take 
place. The tips of the petals begin to turn inwards and become 
thickened, until finally their backs almost meet, thus furnishing a 
close protection about the nascent organs within (Fig. 4a). Look- 
ing down upon the mouth of the corolla tube at this stage, there 
is a striking resemblance to a coral cell, and this likeness is inten- 
sified by the flowers being massed together upon a broad recepta- 
cle.. Then for the first time can it be noted that the contiguous 
edges of the two inner petals are simply in contact but not united, 
except at the very tip, and that the tube enclosing the essential 
organs is a slit one. This slit extends almost to the constriction 
or base of the corolla, the extremely short portion of complete 
tube below representing what in anthesis is to become the true 
tube; while the slit tube investing the essential organs is to be- 
come the strap. In the bud state, therefore, it is the strap that 
Protects the stamens for almost their entire length, strap and 
stamens elongating pari passu. But during anthesis a wonder- 
fully rapid development of the true tube carries the strap part far 
above the stamens. During this rapid pushing upward, the slit 
begins to widen from below, the tips of the two inner petals being 
the last to separate, until finally the flat strap of the completely 
open flower appears. So rapid is this pushing upward of the true 
tube, that one whorl of flowers may have it fully developed while 
the whorl next within will have no indication of its growth. 
Having thus traced the corolla in its development, we will con- 
sider a second and more important change which appears simul- 
et with the constriction that marks out ovary and corolla 
u 
5 the node is seen there appear within five small PINEA. 
which develop rapidly, become oblong, and are soon distinguished 
1 
pam here is an interesting resemblance of the corolla tube in both oe os 
e “OM, to the filament. For the stamens almost fully mature before tha pinne 
°S, Which is done often with great rapidity. 
