168 



MINUTE STRUCTURE OF THE FLOWER. 



470. The fully grown flower of Lysimachia quadrifolia is thus 

 characterized : Calyx hypogynous, deeply 5-parted, the lobes 

 valvate or veiy slightly imbricated in the bud ; corolla hypogy- 

 nous, wheel-shaped, and deeply 5-parted with hardly any tube, 

 its lobes convolute in the bud ; no teeth between the lobes of the 

 corolla ; lobes of the corolla longer than the narrow lanceolate 

 lobes of the calyx ; stamens of unequal length, plainty united at 

 the base, inserted opposite the lobes of the corolla, glandular ; 

 anthers barely oblong ; ovary one-celled, surmounted by an un- 

 divided style and stigma, and containing 10-15 ovules on a 

 central placenta. 



Fig. 126 shows the appearance of a very young flower of this 



species ; on the rounded 

 or somewhat flattened 

 apex of the axis minute 

 elevations are seen, the 

 outer being the nascent 

 sepals. Fig. 127 shows 

 the flower in a more ad- 

 vanced stage. Fig. 128 

 represents a portion only, 

 the right, in a still more 

 advanced condition. 

 Fig. 129 exhibits all the 

 organs of the flower, so 

 far as they can be shown 



FIG. 127. Lysimachia quadrifolia. A longitudinal section through a flower some- 

 what more advanced than in Fig. 126; the letters are the same as in Fig. 128. (Pfeffer.) 



FIG. 128. Lysimachia quadrifolia. Longitudinal section through an elevation which 

 is considerably advanced before the appearance of the petals: st, stamen; n, cells 

 where the petals will appear. (Pfeffer.) 



FIG. 129. Lysimachia quadrifolia. A longitudinal section through a flower in which 

 all the organs are well developed, and even the parts of the ring by which the corolla- 

 lobes are to coalesce have begun to grow : sp, sepal ; p, petal, or corolla-lobe ; at, stamen ; 

 g, ovary ; c, placenta ; sp. u, and p. u, the tissue uniting the parts of the calyx and corolla 

 respectively. (Pfeffer.) 



