194 The Ohio Journal of Science [Vol. XXI, No. 6, 



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lent structures caused staminate and carpellate characters to 

 appear in a mosaic. It is even possible that there are no dis- 

 tinct, general staminate and carpellate factors but common 

 dimorphic factors which produce one type of characters under a 

 female state and another type under a male state. Whatever 

 distinctive factors for carpellate or staminate characters are 

 present are rendered latent or active, depending on the sexual 

 state of the cells involved at the time of development. 



Altho sexual states must be regarded as fundamental to 

 the living cell, probably, of a chemical or physical nature and 

 brought about by an intimate change of materials held in the 

 meshes of the living structure or some change in the living 

 material itself, it is probable that the reactions of the complex 

 hereditary factors to sexual states is essentially similar to other 

 dimorphic reactions; as for example, the difference in char- 

 acters caused by youth and senility, by light and darkness, or 

 some of the striking differences accompanying aquatic and 

 aerial environments characteristic of certain species of water 

 plants. 



The figures from Salix may be briefly explained as follows: 

 Fig. 35 represents a normal staminate flower with five stamens 

 from the lower part of the catkin. Fig. 36 represents a normal 

 carpellate flower with three stigmas and Fig. 37 one with stig- 

 mas from the upper part of the catkin. Fig. 38 is a flower from 

 the lower part of the transition zone with two perfect stamens 

 branching off from the lower part of the ovulary and an abnor- 

 mal stamen coming out of its side. The stalked anthers are the 

 normal yellow after being preserved in alcohol w^hile the sessile 

 anther from the side of the ovulary is of a brownish color par- 

 taking of the nature of the ovulary wall. Fig. 39 represents a 

 bisporangiate flower with stamens developed at various levels 

 from the ovulary wall. Fig. 40 shows one stamen with an 

 enlarged . filament having carpellate ■ characteristics and an 

 imperfect stigma. This flower was at the base of the transition 

 zone next to the normal staminate flowers. Fig. 41 shows an 

 interesting bisporangiate flower with two stamens and a micro- 

 sporangium developed near the top of the ovulary. The stigma 

 just above this microsporangium is much reduced because of 

 the influence of the tissue in the male state immediately below. 

 The other stigma is normal. Fig. 42 represents a bisporangiate 

 flower with one stamen and a microsporangium from the side 



