EVOLUTION OF THE INFLORESCENCE. 517 
the two chief cases taken, viz., those of /Telleborus and Pyrus. He regards a | 
much branched and many flowered panicle as primitive and a less branched, 
fewer flowered one as derived from it by reduction. For example, he looks 
upon the dense inflorescence of Pyrus Aucuparia (the Mountain Ash) as the 
earliest type, and that of P. Cydonia (the Quince) with solitary terminal 
flowers as the latest, among the species dealt with in the genus Pyrus. Lam 
tempted here to apply the Euclidean” phrase “reductio ad absurdum," 
though quite aware that there may be cases where a singly borne flower has 
come from a cluster of many through reduction. 
Ewart *, in a small text-book published in 1907, incidentally refers to the 
relationship of racemose to cymose inflorescences, and considers that the 
former gave rise to the latter. His remarks are not without interest and 
bear reproducing here, 
“In any case it seems probable that all cymose inflorescences have been 
derived from racemose ones by a shortening of the main axis and a delay in 
the development of the lateral branches, to which the main power of growth 
is at the same time transferred. The cymose inflorescence is certainly an 
advance upon the racemose type, for in the former new flowers continually 
appear on the exposed surface of the inflorescence while the fruits ripen 
securely buried among the older parts of the mass of branches.” Further, “if 
the growing point of a young raceme is destroyed, the power of producing 
flowers may be temporarily lost, whereas the destruction of the apex of a 
eyme, involves the loss of a single flower only, and the lateral axes continue 
their growth with even greater vigour than before.” And again, speaking 
of the compound raceme or panicle, he writes: “ This is the most primitive 
type of inflorescence for it is really the modified upper region of the plant, 
whereas the simple raceme is more highly differentiated and has become 
simple by reduction.” 
Hence hidden away in an elementary primer, we have come across 
perhaps the most pronounced views yet expressed on the evolution of the 
inflorescence. Though dissenting from his views in general, yet I am in 
agreement with him in regarding the simple raceme as having come from 
the panicle by reduction, that is, by the loss of the tertiary floral axes. 
It is not the author’s intention to review here the whole of the literature 
dealing with the inflorescence, but only that part which has any bearing on 
the general evolution of flower-grouping. However, as it happens, there 
appear to be few additional papers other than those already alluded to, with the 
exception of those dealing with the morphological elucidation of the puzzling 
inflorescences of the Boraginacese and Solanaces. Of these memoirs, that of 
* Ewart, A. J., * First Stage Botany,’ 2nd Edit. (The Organized Science Series |, London 
1907, p. 127. 
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