DOUBLE FLOWERS. 



43 



radius, the disk of the flower is filled up ; as in Helianthus, 

 Calendula, Chrysanthemum, Anthemis, Matricaria, Ptar- 

 mica, Tagetes, and the species of Centaurea, called Cyan us. 

 In this sort of impletion, which belongs only to radiate flowers, 

 it is observable, that all the florets which fill up the disk follow 

 the conditions of those of the radius; so that if the florets of the 

 radius in the natural flower have a pistillum, all those of the full 

 flower will have one also, as in Matricaria, Bellis, Chrysan- 

 themum, and Tagetes ; or if they have no pistillum, then it will 

 also be wanting in the full one, as in Helianthus, Calendula, 

 and Centaurea ; and the same holds true of the male part also • 

 for as the florets of the radius in the natural flower are never fur- 

 nished with antherse, so thesq are wanting also in all those of 

 the full ones. This last remark is of great use to distinguish a 

 radiate full flower, from a ligulate natural one ; which might be 

 confounded in many cases, were we not apprised that there are 

 antherae in the latter, but none in the former; by this rule in 

 Chrysanthemum, Helianthus, Calendula, and Tagetes, when 

 the disk is destroyed by the multiplication of the radius, we know 

 by the defect of anthera?, that it is only the luxuriancy of a ra- 

 diate flower, as in Hieracidm, Leontodon, and Sonchus; by 

 the presence of the anthera? we know the flowers to be ligulate 

 and natural. 



Impletion by the disk is, when there is no multiplication of 

 the radius ; but the corollulee of the disk run out into length, and 

 have their brims less divided : this manner of impletion seems to 

 concern only the radiate and the tubulose*. In the radiate, it 

 will so far affect the radius, as to change its flowers from ligulate 

 to tubulose : instances of this manner of impletion may be had 

 in Bellis, Matricaria, and Tagetes. In the Carduus of the 

 oats, which is a species of Serratula, the corollulae are both 

 lengthened and enlarged. In respect to the ligulate flowers, if 



* This is not expressly asserted, as the distinction is omitted in the Philosophia 

 Bo) anica of Liiunceus ; but it appears to be his meaning, by his speaking of the im- 

 pletion of ligulate flowers separately afterwards. 



