THE INFLORESCENCE, AND THE FLOWER 



!35 



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 ;i vestigial stamen 

 {st.) is seen in Scrophidaria (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 anion r 

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

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

 precision of the floral mechanism. For instance in the Orchidaceac, deriveti 



Fig. i83ftjs. 



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

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

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

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

 Valerianaceae show various degrees of abortion of the stamens ; but they also 

 have a reduced gynoecium. Here also three locuh are present in the ovary, but 

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

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

 carpels, 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 m the 

 Scrophulariaceae. The flower is typically pentamerous. but it bocomes 

 reduced to apparent tetramery. In the Mullein {Verbascum) the formula 

 is Sg, Pg, Ag, Gg. But in Scropkularia the posterior stamen is represented 



