114 TEE FLOWER 



as ill possessing wliat answer to the veins or libs of leaves, 

 — librous elements couiing' out from the flower stem. 

 Occasionally stamens and pistils are found which have 

 failed to develop in their proper character. Tiiey then 

 take the shape of foliage leaves, more or less exactly. 

 The conclusion is inevitable, from all these considerations, 

 that the essential organs of the flower, as well as the floral 

 envelopes, are morphologically leaves.^ 



219. The carpels, in this conception, become leaves rolled inward, 

 lieariug un the inrolled edges rows oJ: ovules. When the pistil is 

 simple (ol one carpel or leaf), a seam, the retitnd suture, mark.s the 

 closing together of the ovuliferous leaf on the side toward the center 

 of the flower ; while a I'idge up and down the opposite side of the pis- 

 til evidently stands for a midrib. 



220. Departures from a simple floral plan. — If one were to examine 

 the first score of different flowers that he should meet on going into 

 tlie field, he would prol>ably find among them few or none that display 

 the regularity, simplicity, and completeness spoken of in § 2X1 . The 

 fundamental plan — that is, tlie order and mode of growtli, num- 

 ber of parts, etc. — would be found in many cases to be obscured 

 by a variety of adaptations to the special functions of the flower. 

 Some of the commonest modifications to be discovered are the 

 following : — 



221. Absence of some of the organs.'-' — Occasionally the gradual dis- 

 appearance of some of the organs may be directly noted, as in stamens 

 lacking the anther, or reduced to a mere ridge or rudiment; or in tlie 

 reduction of one whorl of the periantli to an inconspicuous ring. In 

 many of the trees and shrubs the perianth will be found to consist of 

 only the cah'X {e.g. in the Elm), or it may even be wanting {e.fj. in the 

 Buttonwood). And two cases liave already been mentioned (the Wil- 

 low and the Pine) where each flower contains but one kind of essen- 

 tial organ. 



222. Union of like parts, or coalescence, of which examples iiave 

 been given above. 



1 This is not to be construed to mean Ihat what were once merely 

 foliage leaves have in the course of time been modified so as to become 

 carpels, stamens, etc. All that is to be inferred here is that both foliage 

 leaves and floral organs have a common morphological nature, as foliar 

 appendages of tlie stem. 



- It is possible to suppose in some cases that the fewness of parts, or 

 the absence of certain organs, has come about, not by reduction from 

 more highly organized forms, but by inheritance from ancestry charac- 

 terized by simple flowers from the first. 



