CHAP. 11. 
COROLLA. 
139 
appendages^ and such a calyx is said to be appendiculate ; but 
Moench has proposed a particular term for them, peraphyllum^ 
which is, however, never used. 
7. Of the Corolla. 
88 89 90 91 
That envelope of the flower which forms a second whorl 
within the calyx, and between it and the stamens, is called the 
corolla. Its divisions always, without exception, alternate 
with those of the calyx, and are called petals. Like the 
sepals, they are either united by their margins, or distinct; 
but, unlike the calyx, they are rarely green, being for the most 
part either white, or of some colour, such as red, blue, or 
yellow, or of any of the hues produced by their intermix- 
ture. The corolla is generally also much larger than the calyx. 
Necker called the corolla perigynandra interior, and Lin- 
naeus occasionally gave it the name of Aidceum, which literally 
signifies the drapery of a room. 
The alternation of the segments of the corolla with those 
of the calyx is a necessary consequence of their both being 
modifications of whorls of leaves, and therefore subject to the 
same laws of arrangement. If two whorls of leaves are exa- 
mined, those of Galium, for example, they will always be 
found to be mutually so arranged, that if the internode that 
separates them were removed, they would exactly alternate 
with each other ; and as there are no known exceptions to this 
