STRUCTURE OF FLOWERS. 71 



each carpel may be considered as formed of two partial 

 styles, sometimes perfectly free, at others more or less 

 united together ; and then we say that it is bifid, and 

 that it has two stigmata. The Euphorbiacese show very 

 well these different states of the carpellary styles, both 

 simple and forked. 



When the styles are detached or raised above the 

 carpels, they are most frequently free ; at times united 

 with the central column, as in Geranium. 



The stigma is, as we have said, a kind of spongiole 

 supported by the pistil. It is usually situated at the 

 extremity of the carpellary styles, and we say that there 

 is but one when they are united the whole way, and that 

 there are two when they are only united part of their 

 length. This manner of expression has often caused the 

 branches of the style to be confounded with the stigmata, 

 which in reality are only the glandular part, whatever 

 place it occupies. Thus, for example, in several Legu- 

 minosae this portion is naturally near the extremity ; in 

 the Iris the branches of the style are flat, petaloid, and 

 two-lipped, the upper very long and often bifid, the 

 lower very short; it is in the transverse fissure which 

 results from the position of these two lips that the glan- 

 dular part or true stigma is found. 



The stigma, whatever be its position and form, is be- 

 set with viscid papilla?. The pollen, when it falls upon 

 it, experiences the action of this humidity — it bursts ; 

 the fovilla is absorbed by the spongioles, and on applying 

 coloured fluids to them, as Bulliard did, we see that they 

 follow the vessels in the interior of the style, penetrate 

 into the placenta, and thus reach the ovules. It is by 

 this means that vegetable fecundation is performed. 

 The collection of vessels which go from the stigmata to 

 the seeds bears the name of the Pistillary Cord ; we 

 shall revert to it on speaking of the fruit. 



