288 PHARMACEUTICAL BOTANY 
SUTURAL PLACENTATION is seen in the Leguminose (Pea, Bean, 
etc.). Here each carpel has prolonged along its fused edges two 
cord-like placental twigs, from which start the funiculi or ovule 
stalks. 
PARIETAL PLACENTATION is seen in Gloxinia, Gesneria, Papaver, 
etc. Here we find two or more carpels joined and placental 
tissue running up along edges 
of the fused carpels bearing the 
ovules. 
CENTRAL OR AXILE PLac- 
ENTATION is seen in Campanu- 
lacee (Lobelia, etc.), Solanaceae, 
etc., where the two, three, or 
more carpels have folded in- 
ward until they meet in the 
center and in the process have 
carried the originally parietal 
placenta with them. This then 
Fic, 217.—Heterostyly, a means of may form a central swelling 
insuring cross pollination. Two forms of : 
flowers of bluets (Houstonia) opened out bearing the ovules over the 
and seen from the inside. A, short surface. 
stamens and long style. 2B, long stamens FREE CENTRAL PLACENTA- 
and short style. An insect visiting A, will TION occurs perfectly in the 
receive pollen upon the front part of its 
body; upon visiting B this pollen will rub Prémulacea, Plantaginacee and a 
against the stigmas, and the pollen from few other families. In this the 
this flower will be received by the under carpels simply cover over or 
part of the body; upon visiting another : n 
flower like A, the pollen from B will be FOOfin a central placental pillar 
brushed against the stigma of A. (From around which the ovules are 
Darwin’s “Cross Pollination.”? Courtesy of scattered. 
my cote & Ce.) StyLE.—The style is the 
portion of the carpel which connects the stigma with the ovary. 
It is usually thread-like but may also be considerably thickened. 
It frequently divides into branches in its upper part. These are 
called Styte Arms. As many style arms as carpels may be 
present. In the one-carpelled pistil of some Leguminosae, the 
usually bent-up style is the tapered prolongation of a single 
flower. Again, in the apocarpous carpels of many flowers of the 
Ranunculacee, each carpel bears a short to long stylar prolonga- 
tion, When the carpels, however, are syncarpous, the common 
