UBTIGAGE2E. 



505 



posed ; eacli has a free filament of variable form 1 inserted under the 

 ovary, and an introrse two-celled anther of longitudinal dehiscence. 

 The gynaeceum, inserted on the conical apex of the receptacle, 

 consists of a one-celled uniovulate ovary, analogous to that of the 

 Nettles, surmounted by a slender style, articulated at the base and 



Parietaria officinalis. 



Fig. 543. 

 Hermaphrodite flower (&). 



Fig. 542. 

 Flowering branch. 



Fig. 544. 



Long. sect, of female 

 flower (|). 



caducous, with a stigmatiferous head, whose unilateral investment 



with long papillose hairs gives it the look of a bottle-brush 



(figs. 543, 544). The female flowers possess only a gynseceum, 



closely surrounded by the tubular gamosepalous calyx. The males 



have a shorter calyx, with the leaves free or nearly so, lined with 



hairs, close to the base of a rudimentary gyna3ceum. Against this 



are applied the anthers, while their filaments are strongly bent in 



the bud ; on anthesis they become straight by elasticity. The fruit 



(figs. 545, 540) is a straight somewhat compressed achene, smooth 



and shiny,' 2 enveloped in the persistent calyx. The orthotropous 



seed, formed nearly as in the Nettles, has a cylindro-conoidal 



embryo, of nearly the same length as the cotyledons, which are 



1 When the anthers are retained at the centre 

 of the male bud, either by the rudimentary 

 gynseceum or by the hairs at the bottom of the 

 perianth, the filament thickens during this incur- 

 vation, and then there form on its inner face the 

 superposed transverse ridges alternating with 

 grooves. To the turgescence of these bars is due 

 the elastic rising of the filament. But when the 



filaments are shorter, not incurved, but erect and 

 straight, which is the case in some flowers that 

 are female or more or less completely herma- 

 phrodite, no transverse band is developed on 

 the inner face ; it remains smooth like the outer 

 one, and no phenomenon of elasticity takes place. 

 2 Green, more or less dark in colour, according 

 to the age. 



