PHARMACEUTICAL BOTANY 
198 
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 con¬ 
siderably thickened. It frequently divides into branches in its upper 
part. These are called style arms. As many style arms as carpels 
may be present. In the one-carpelled pistil of some Leguminosce, the 
usually bent-up style is the tapered prolongation of a single flower. 
Again, in the apocarpous carpels of many flowers of the Ranuncul- 
acece, each carpel bears a short to long stylar prolongation. When 
the carpels, however, are syncarpous the common styles tend to 
become more or less fused but usually show lobes, clefts or style 
arms at their extremities that indicate the number of carpels in 
each case which form the gynoecium. 
In some plants remarkable variations from the typical stylar 
development may occur. Thus, in Viola, the end of the style is a 
swollen knob on the under surface of which is a concave stigma with 
a flap or peg. In the genus Canna the style is an elongate blade-like 
flattened body with a sub-terminal stigma. In forms of the Cam- 
panulacece the style is closely covered with so-called collecting hairs. 
On these the anthers deposit their pollen at an early period before 
the flowers have opened. Later, when the flowers open, insects 
remove the pollen after which the collecting hairs wither. The stig¬ 
mas then curl apart to expose their viscid stigmatic hairs. In this 
instance there are two distinct and at separate times functioning 
hairs on the stylar prolongation, viz.: ( a ) collecting stylar hairs, 
functioning for pollen collection and distribution; and ( b ) stigmatic 
hairs for pollen reception from another flower. In Vinca the style 
swells near its extremity into a broad circular stigma and then is 
prolonged into a short column bearing a tuft of hairs that prevents 
the entrance of insect thieves into the flower. In the genus Iris 
the common style breaks up at the insertion of the perianth into 
three wide petaloid style arms. Each of these bifurcates at its ex¬ 
tremity. On the lower or outer face of this is a transverse flap that 
bears the stigmatic papillae. In Physostigma the style enlarges at 
its extremity into a flap-like swelling which bears a narrow stigmatic 
surface. Finally in Sarracenia the single style of the five-carpelled 
pistil enlarges above into a huge umbrella-like portion with five 
radiating ribs. At the extremity of each bifid end of each rib is a 
minute peg-like stigmatic surface. 
