Il6 BOTANICAL GAZETTE [august 



not pushed up above the calyx lobes. The writer has examined 

 at least loo plants with this closed corolla type of flowers. In 

 every case the stamens were scarcely or not at all exserted and. 

 were completely composed of sterile tissue. 



Thus far all plants that I have seen which had completely 

 sterile non-exserted stamens also had closed flowers; but the 

 pistillate form as described by Bartlett also includes plants 

 with corollas fully developed and reflexed, and . such a flower is 

 figured by him (2, fig. 3) as illustrating a typical pistillate flower. 

 Various plants with expanded petals and completely sterile 

 or indehiscent stamens are potentially only females. The rudi- 

 mentary development of stamens and the character of the corolla 

 may be regarded as extreme cases of loss of maleness, and the 

 character of the corolla may be considered as a secondary sex 

 character associated with femaleness and appearing when male- 

 ness is most completely lacking. 



From general observations of plants in the field and in a green- 

 house, and from such controlled pollination as have been made, it 

 appears that plants of this pistillate type are highly productive 

 of seed. A few plants, however, have set no seed when exposed 

 to favorable conditions for free cross-poUination, which suggests 

 that the pistils of some of the pistillate plants may be impotent. 



These descriptions refer to the types of flowers that charac- 

 terize the 3 forms most generally recognized, and into which 

 attempts have been made to classify all individuals. Both Cor- 

 RENS (4) and Bartlett (3), however, recognized that it was 

 somewhat difficult to thus place all individuals observed by them. 

 Such a difficulty has been very apparent in respect to the material 

 studied by the writer. The variations present almost every grade 

 of intermediates between the two extremes described, and seem 

 to involve a series of sex intergrades or intersexes. The character 

 of flowers may be quite uniform for a plant as a whole, or there 

 may be a wide range of intersexuality among the different flowers 

 of a single spike, or even among the various stamens of a single 

 flower. Flowers typical for some of these may be described and 

 arbitrarily numbered as follows: 



