Structure, etc., of Epiphegus Virginiana. 383 



upper part this may often increase to a considerable cav- 

 ity, so that in efifect there are two styles present. If styles 

 are forcibly compressed under a cover-glass, they split read- 

 ily in two along their entire length. In some cases the 

 stigma also shows this bifid nature. In one flower that was 

 sectioned, the style forked in two in the middle of its course, 

 and each of these two styles bore its own separate stigma. 



It is interesting to observe the special arrangements of 

 style and stamens so as to provide for cleistogamy. The 

 small cavity within the cap-like corolla is nearly filled up 

 by the four stamens and the style. There is little free space 

 left. The style rises at the extreme posterior region, passes 

 upward and curves forward (Fig. 4), close under the 

 broader arch of the cap-like corolla. Anterior to the style 

 rise the four stamens, two on each lateral wall, curving 

 inward toward the stigma. In an older cleistogamic flower, 

 the style has curved more strongly forward ajid then down- 

 ward again. The broad stigmatic surface now lies facing 

 forward and somewhat downward. The filaments have 

 pulled the anthers downward by a peculiar twisting and 

 bending on themselves. So now the two anther lobes of 

 each stamen are seen closely appressed against the stigmatic 

 surface. The stigma lies with two anthers pressed against 

 it on both sides. Great numbers of pollen tubes are seen 

 passing from the anthers over into the stigma. Such a 

 close attachment is formed that it is impossible to tear the 

 anther away from the style without completely destroying 

 the tissues of both structures. 



Evidently the peculiar form of the corolla, resembling in 

 shape a liberty cap as nearly as anything, depends upon the 

 positions of pistil and stamens. The broad convex surface 

 of the cap is the surface overlying the curving style. The 

 shorter face of the cap indicates the curving planes along 

 which the stamens are ranged. 



This peculiar arrangement of style and stamens supplies 

 the explanation for the greater seed production in one valve 



