PHANEROGAMIA : FLOWERS. 



329 



circle that belong to one and the same part of the flower, as, for instance, 

 the stamens, to reckon up the amount even for the greater number. 



Close to those just named comes another condition, though far more 

 rarely ; where, namely the individual parts of the flower, either through 

 the entire flower* or from the stamens forward, as in the Ranunculacece, 

 or the carpels, as in the Dryadece, arise, one after another, in a spiral 

 around an axis then mostly very much developed, and thus become 

 perfected in succession. Here it is never specifically determinate, but 

 only individually, with which members of the spiral, another form of 

 the foliar organ shall enter, for instance, the stamens be converted 

 into carpels ; nor what shall be the greater number of foliar organs 

 contained in the spiral ; consequently, shall complete the entire flower. 

 The plants here referred to are properly characterised as possessing 

 indefinite parts (partibus indefinite). In this way the said expressions 

 of descriptive botany, which had been selected through a distinctly-felt 

 necessity, and by a practical perception of nature, acquire, through the 

 investigation of development, a rigid, scientific meaning which they 

 really did not possess before, since no one could rightly say what paries 

 definite and indefinite actually were. 



b. The second point to which I desire to draw attention is the varied 

 development of the members of one and the same circle, in which they 

 assume forms such, that we are tempted to separate them entirely from 

 the circles to which they belong ; where, for instance, in the corollary 

 circles some leaves become, if we may so say it, stamens ; and in the 

 staminal circles some become petals, accessory petals, or accessory stamens; 

 or, in the carpellary circles, some become stamens, and some accessory 

 stamens. One of the most striking examples 

 of this is offered by the fourth and inner- 

 most tri-merous circle of Canna (fig. 195.). 

 Properly all three parts should become car- 

 pels, and form the style ; but one alone is folded 

 in to form the style ; a second becomes the 

 stamen ; and the third is wholly abortive, but 

 exists in the tolerably large bud on a small 

 scale, not very easy to represent. (See Plate III. 

 fig. 12., with the explanation.) 



Many of the Orchidacece furnish known 

 examples of the same fact, in which only one 

 or two leaves of the innermost circle but one 

 become stamens ; whilst one or two, if they are 

 not totally abortive, develope merely into small 

 scales or glands. I may add, that something 

 similar occurs in the generality of the Scita- 

 minece, but I have not had opportunity to 

 follow out fully the history of the development. 

 The Balsaminece may, perhaps, be explicable 

 in the same way, but I have not yet succeeded 

 in detecting their earliest conditions with suf- 

 ficient clearness. When the entire bud has 

 reached only the length of from one-eighth to 

 one-sixth of a line, the flower already has its 

 contour almost as irregular as subsequently. 



* Although I cannot bring forward any certain example of this, probably in the 



species of l\f<iynli<i and some l\<n/Kcu/ftcc, especially the Ainmniii'ir. 



195 Canna exigua, developed flower, a. Inferior get men ; />, calyx ; c, external, and 

 </, inner circle of the corolla ; e, stamen* ; e', style. 



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