THE INFLORESCENCE, AND THE FLOWER 



235 



parts which comparison with allied plants would show as actually 

 present. Sometimes those parts are represented by vestigial remains, 

 marking the position which those parts should hold, though they do 

 not come to functional maturity. A good case of a vestigial stamen 

 (st.} is seen in Scrophularia (Fig. 183). 



Meiomery may appear in any of the floral parts ; often it is seen in several of 

 them in the same flower. A complete whorl may be absent : for instance the 

 corolla in the Pearl- Wort (Sagina apetala) in the Pink Family, or Glaux among 

 the Primroses : or one of the whorls of stamens may be absent, as in the Prim- 

 .rose. The most marked examples in the androecium are related to increasing 

 precision of the floral mechanism. For instance in the Orchidaceae, derived 



FIG. 183 bis. 



am an Amaryllidaceous type with six stamens, Anastasia has three, 

 Zypripedium two, and Orchis only one the anterior stamen. Ginger has also 

 ily one, but it is the posterior. All of these are highly specialised types : 

 leir meiomery by abortion has followed parallel, but quite distinct lines. The 

 /alerianaceae show various degrees of abortion of the stamens ; but they also 

 ive a reduced gynoecium. Here also three loculi are present in the ovary, but 

 ily one bears a fertile ovule. The same is the case in the Oak ; also in the 

 co-Nut. Here the three depressed scars on the shell indicate the three 

 irpels, but only the one that can be pierced by a pin matures its seed, and 

 forms a germ. 



A beautiful case of meiomery, involving several steps, is seen in the 

 :rophulariaceae. The flower is typically pentamerous, but it becomes 

 luced to apparent tetramery. In the Mullein (Verbascum) the formula 

 S 5 , P 5 , A 5 , G 2 . But in Scrophularia the posterior stamen is represented 



