516 MR. J. PARKIN ON THE 
of inflorescence and endeavours to connect them one with another, but he 
expresses no clear views as regards the general way in which the evolution 
of flower-clusters has taken place. 
An extensive memoir by Hy*, published in 1894, is mainly descriptive with 
little evolutionary bearing, but is from the point of view of classifying in- 
florescences of distinct value. He has, however, much to communicate about 
intermediate types of inflorescence (inflorescences de passage), and apparently 
would derive indefinite (racemose) from definite (eymose) inflorescences, 
since one of the sections of his paper is headed “ Passage de inflorescences 
definite à indefinite." 
Arber T, in 1899, confining himself to a consideration of indefinite inflores- 
cences, endeavours, by the application of his “ theory of internodes,” to upset 
eurrent notions respecting the inter-relationship of the various forms of this 
kind of flower-grouping. Instead of regarding the spike, umbel, capitulum 
ote., as derived from the raceme by internodal suppression—the view usually 
held—he puts forward the opposite idea, and would obtain, for example, the 
raceme from the spike and the umbel from the capitulum by means of inter- 
nodal elongation. Personally, I see no reason for departing from the 
prevailing view, except in so far that a splke may occasionally arise from a 
spicate cyme, this in its turn having come from a panicle. The same may 
also sometimes happen in the case of umbels and even heads. That is to say, 
the inflorescence has undergone internodal suppression before and not after 
it has become truly racemose. 
In Engler's ‘Syllabus der Pflanzenfamilien, 1907 f, a short section is 
devoted to the consideration of the Inflorescence. He writes that the racemose 
type cannot be placed higher than the cymose or vice versa, particularly as 
both permit themselves to be derived from a panicle. My reply to this would 
be that a panicle in its simplest form is nothing but a eyme, and in its more 
complicated form a transition to a true raceme. He also writes that inflores- 
cenees which are phylogenetically the furthest advanced, are those which are 
so complicated as to resemble a hermaphrodite flower, e. g., those of many 
Araceæ and Wuphorbiaceæ. With this I am in complete agreement. ` 
Chureh's admirably conceived work, ‘Types of Floral Mechanism ' $, 
claims some attention here, as he has ventured, in his treatment of some of 
the genera selected for study, to deal with the inflorescence from an evolu- 
tionary standpoint. The views he expresses run directly counter to mine in 
* Hy, H. F., “ Les Inflorescence en Botanique Descriptive," Rev. Gén. de Bot. vi. (1894) 
p. 385, 
T Arber, E. A. N., “ Relationships of the Indefinite Inflorescences,” Journ. Bot. xxxvii. 
(1899) p. 160. 
I Engler, A., ‘Syllabus der Pflanzenfamilien, 5th edit., 1907. 
$ Church, A. H., * Types of Floral Mechanism, Oxford, 1908, pp. 10-13 & 182. 
