XIV] FLORAL FORMULA 129 



In cases where the calyx (K) and corolla ((7) cannot 

 be distinguished, we can use the letter P to denote 

 Perianth, and the formula 



for instance, would indicate that our flower had a peri- 

 anth of three separate parts, six stamens in two alternating 

 whorls of three each, alternating with these parts and with 

 the three united carpels of a superior syncarpous pistil. 



But suppose some of the organs were too numerous to 

 be worth recording : the sign oo for indefinite would then 

 indicate this as follows : 



K 5 C 5 A x G., 



which would show that our flower e.g. a Buttercup 

 (Fig. 33) had a calyx of five free sepals, a corolla of five 

 free petals, an androeciurn of an indefinite number of free 

 stamens, and a pistil composed of numerous free carpels. 



If we now take the case of a flower such as that of a 

 Laburnum, several points of difference from the above 

 appear. Its calyx is gamosepalous, its corolla is zygo- 

 morphic, its ten stamens are joined in a tube, and it has 

 but one free carpel. All this is easily expressed in the 

 floral formula as follows : 



K ( ^C 5 A M 01, 



the ( ) indicating the gamosepaly of the calyx, and the 

 concrescence of the stamens ; the { indicating that the 

 corolla is zygomorphic in the median plane ; and the G 1, 

 that there is but one free carpel. 



Similarly the floral formula of the Bittersweet 



K 0^4. 0(2) 



indicates by the linking N that the stamens are in- 

 serted on the corolla. 



w. in. 9 



