THE STRUCTURE OF FLOWERS. 51 



Again, the filaments of the stamens may cohere/ 

 as in most flowers of the pea family, Leguminosce, in 

 which the anthers are free, but in the great family well 

 known for its Everlastings {Coinpositm), this condition 

 is reversed, in that the filaments are free from each 

 other, but the anthers alone cohere, forming a little 

 cylinder (Fig. 67, IL, III.), through which the style 

 passes. It is the same in Lobe'lia (Fig. 14, II.). 



In the majority of flowers the carpels of the pistil 

 cohere. This is easily seen by cutting the ovary 

 across, when two or more cells will be usually seen. 

 In the many bulbous plants^ the ovary will almost 

 invariably be found to have three cells. In Pdargo'nium 

 there are five (Fig. 12, III.), and in the bell-like flower 

 of Bocl'lcL only two (Fig. 11, IV.). 



In some few flowers there is only one ovary-cell, 

 though it may be composed of two or more carpels. 

 This is explained by taking, say, three pea-pods, 

 splitting them down, along one edge only, called the 

 placenta, which carries the peas ; then placing the three 

 together, edge to edge, a hollow chamber would be 

 formed having three rows of peas (really six, each 

 being composed of two). In some such ovaries there 

 is only one ovule which arises at the base of one of 

 the placentas ; so it appears to spring from the middle 



1 The ten stamens of Ox'alis cer'nua are sliglitly joined at the 

 base of the filaments (Fig. 16). 



- For figures, see under the family Liliacex. 



