DA COHESION 
in which one of the petals had the form of a cup sup- 
ported on a long stalk. This cup-shaped organ was 
placed at the back of the flower, and had the dark 


Fie. 9.—LHranthis hyemalis. Transition from flat sepal to tubular petal. 
colour proper to the petals in that situation. I have 
seen a petal of Clarkia similarly tubular, while some of 
the cultivated varieties of Primula sinensis exhibit 
tubular petals so perfect m shape as closely to re- 
semble perfect corollas. 
Like the petals, the stamens, and even the styles, 
assume a hollow tubular form. This change of form 
in the case of the stamens is, of course, usually attended 
by the petaloid expansion of the filament, or anther, 
and the more or less complete obliteration of the pollen 
sacs, aS in Fuchsias, and in some double-flowered 
Antirrhinums.’ So also in some semi-double varieties 
of Narcissus poeticus, and in Aquilegia. By the late 
Professor Charles Morren, this affection of the stamens 
and pistils was called Sole anne but as a similar con- 
dition exists in other organs, it hardly seems worth 
while to adopt a special term for the phenomenon, as 
it presents itself in one set of organs. 
In many of these cases it is difficult to say whether 
the cup-like or tubular form is due to a dilatation or 
hollowing out of the organ affected, or to a fusion of 
its edges. The arrangement of the veins will in some 
' * Report of Internat. Bot. Congress,’ London, 1866, p. 131, tab. 
vii, figs. l1O—13., 
2 «Bull. Acad. Roy. Belg.,’ t. xviii, 2nd part, p. 179. 
