CHAP. II. 
INFLORESCENCE. 
161 
nodal cyme as the type of the cymes of dicotyledonous 
plants. 
X. The helicoid cyme has a straight pseudothallus, not 
excentrical, often vertical. 
XI. The scorpioid cyme has its pseudothallus rolled in a 
plane, excentrical, often horizontal volute, the two rows of 
flowers regarding the sky. 
XII. A cyme may be either axillary or terminal. By de- 
composing the last into partial axillary cymes, we often ar- 
rive at the discovery upon the latter of the laws which the 
entire cyme did not olfer. 
XIII. The multinodal cyme, with axillary cymes, and sub- 
ject to this decomposition, is sometimes rather difficult to 
distinguish from the thyrse. If the axillary cymes are one- 
flowered, there may be a difficulty in distinguishing them 
from the spike. 
XIV. Cymes have another method of centrifugal evolu- 
tion by the developement of accessory peduncles ; these pe- 
duncles are of the same order as those which are born upon 
other nodes of the central peduncle, and are almost always 
antidromal. 
XV. Sarmentidia follow in their organisation the same 
laws as the cyme. 
In this memoir of the Messrs. Bravais there is much which 
is ingenious ; but their system is founded upon theoretical 
refinements, which require further consideration, and much 
simplification, before they can be advantageously applied to 
practical purposes. 
6. Of the Calyx. 
The calyx is the most exterior integument of the Flower, 
consisting of several verticillate leaves, either united by their 
margins or distinct, usually of a green colour, and of a ruder 
and less delicate texture than the corolla. 
Authors have long disputed about the definition of a calyx, 
and the limits which really exist between it and the corolla: 
the above, which is copied from Link, seems to be the only 
M 
