SYMMETEY OF THE FLOWEE. 



91 



bear within a small concave plate, which is a deduplication of the petal. The petals 

 of Ranunculus (fig. 237) bear at their inner base a small scale, parallel to the claw, 



474. Geranium. 

 Diagram. 



475. Erodium. 

 Flower (mag.), without corolla. 



477. Flax. 

 Androscium and pistil (mag.). 



and forming with it a nectariferous cavity ; the bilabiate petals of Helleborus are 

 formed of two nearly equal plates, a,nd may be regarded as originating by dedupli- 

 cation in a parallel direction. The petaloid laminae of these plants must not be 

 confounded with the different protuberances on the corolla of Comfrey (fig. 269), and 

 other Boraginecs, nor with the sort of hairy palate on the lower lip of Snapdragon 

 (fig. 285) and Linaria (fig. 286) ; which are not the result of deduplication, but 

 are derived from the substance of the petal. Deduplications are chiefly confined to 

 the corolla and andrcecium ; they rarely occur in the pistil ; in Sedum (fig. 455) 

 there is externally at the base of each carpel a little green glandular scale, parallel 

 to the carpel, and which might be looked upon as a deduplication of this. 



Deduplications are not always a proof of superfluous vital action ; they may arise 

 from a misdirection of vegetative force ; in fact, when one whorl is doubled, the 

 succeeding one is either weakened, modified, or suppressed, as in the Primrose, Pim- 

 pernel (fig. 479), and other Primulacecs, which have only five stamens, and these 

 opposite to the petals, thus not forming a normally whorled andrcecium, but being 

 referable to a parallel deduplication of the petals ; they thus replace the normal 

 andrcecium, which however sometimes appears, not as stamens, but as 

 scales, alternating with the petals (Samolus, fig. 480). In the Vine 



478. Mignonette. 

 Corolla (mag.). 



470. Pimpernel. 



Stamen 

 and petal (mag.). 



480. Snmolus. 

 Portion of corolla and 

 androecium (mag.). 



482. Rocket. 

 Androecium. 



(fig. 481), the five normal stamens are replaced by five nectaries, but fertilization is 

 secured by five stamens opposite to the petals. 



Collateral deduplication is less frequent than parallel ; in the Rocket (fig. 482) and 



