POSITIVE DEDOUBLEMENT. 



77 



pappus-hairs in the normal hermaphrodite flowers, but 

 of those of the female flower. That the extra pappus 

 is not, as would naturally be at first supposed, the 

 result of dedoublement of the normal pappus, but in 

 all probability arises from dedoublement of the corolla, 

 seems indicated by the fact that the observer noted in 

 another floret supernumerary petals, free down to the 

 middle of the corolla, and each terminating in a fringe 

 of pappus-hairs. These represented, therefore, tran- 

 sitional forms between normal petals and pappus-hairs. 

 Beauverd has seen a similar phenomenon to the above 

 in L. sinense and L. Evax var. fimbrilligerum. 



Another and striking method by which the number 

 of petals is increased, and which may naturally be 

 considered in this place, is that employed by those 

 flowers whose axis becomes more or less elongated 

 beyond the normal, the apex constantly adding new 

 petals to the flower, as in the double cherry, in some 

 flowers of which fresh petals are formed above the 

 carpels ; Goebel cites the formation of fresh petals 

 above the petaloid carpels in Lobelia Erinus. A very 

 extreme instance is afforded by those flowers which 

 exhibit " petalomania," as in the abnormal madonna- 

 lily (Lilium candidum) figured by Masters ; here the 

 floral axis is very greatly elongated so as to resemble 

 a shoot ; not only have all floral members become 

 changed into perianth-leaves, but the apex of the axis 

 has indefinitely added new petals to the whole ; all 

 these petals are, however, very much smaller and 

 narrower than in the normal flower. 



Collateral dedoublement may proceed in various ways: 

 either the petal-rudiment may divide into two approxi- 

 mately equal parts, or it may cut off one or more smaller 

 segments from itself, each of which becomes a complete 

 petal, as has been observed in a stock (Matthiola 

 incana) in which there were six petals : each of the 

 extra small petals was still united laterally to its parent- 

 petal at the base ; this represented the first stage in 

 doubling, to which this flower is very subject, Goebel 



