CHAP. II. 
INFLORESCENCE. 
159 
some of the masses of inflorescence loses its flowers ; but at 
the same time acquires the property of twining round any 
object within its reach, and so of supporting the stem, which 
is too feeble to support itself. Such rachises form what is 
called a spurious cirrhus, or a cirrhus peduncularis^ and are a 
striking exception to the general law that the cirrhus takes its 
rise from the petiole or midrib. 
In the preceding account of the inflorescence I have treated 
the subject as heretofore, because it appears upon the whole 
more convenient to do so for the present, notwithstanding the 
recent ingenious observations of the Messrs. Bravais. 
These botanists, together with Messrs. Schimper and Braun, 
and some others, led by their examination of the spiral ar- 
rangement of leaves into an investigation of the laws that 
regulate the arrangement of flowers, have proposed a new 
nomenclature and theory, of which the following is their own 
abstract {^Ann. Sc.^ N. S., viii. 28.) : — 
I. The inflorescence is a union of flowers grouped together 
in mutual relation. It may often be divided into other 
groups, essentially homogeneous with respect to each other, 
and which we call partial inflorescences ; these inflorescences 
may sometimes be themselves subdivided ; but something ar- 
bitrary may be sometimes found in the manner of their de- 
composition. 
II. The flowers, or partial inflorescences which perform 
the part of them, have two distinct modes of evolution ; the 
centripetal and the centrifugal. 
III. The Spike* is a centripetal inflorescence. (Plan- 
tago, Ribes, Leontodon, &c.) 
IV. The Compound Spike is centripetal, with two de- 
grees of evolution ; thus it is composed of partial inflorescences 
arranged centripetally, and these partial inflorescences are 
spikes. (Male flowers of Pinus.) 
V. The Cyme f is a centrifugal inflorescence. (He- 
* Any centripetal group whatever, such as a partial umbel, raceme, 
spike, capitulum, provided the peduncles are destitute of lateral bracts. 
f A centrifugal group, whose peduncles grow out of each other. 
