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



the narrow-leaf species. A specimen was looked for in which 

 there would be an invasion of one area into the other. Such a 

 specimen was readily found. The one studied had a patch of 

 staminate flowers on one side at the top of the carpellate part 

 of the inflorecsence. On the transition zone flowers of an inter- 

 mediate nature were common. Fig. 5 represents a typical 

 carpellate flower with its prominent stigma and Fig. 6 repre- 

 sents a typical staminate flower consisting of one stamen. The 

 staminate flowers have from one to six stamens. Fig. 7 repre- 

 sents one of the intermediate flowers. The ovulary is unde- 

 veloped but there is a nearly normal stigma at the top and two 

 imperfect microsporangia with spore tetrads. Fig. 8 is a double 

 structure, the one part being a nearly perfect anther while the 

 other has a microsporangium on one side and an imperfect half 

 stigma on the other. 



Arisaema triphyllum (L.) Torr. Jack-in-the-pulpit. 



A certain per cent of the inflorescences of Jack-in-the-pulpit 

 are of an intermediate nature being staminate in one part and 

 carpellate in another. The ''spotting" of the staminate and 

 carpellate areas is quite diverse. Sometimes the spadix is car- 

 pellate below and staminate above; sometimes, the reverse; 

 sometimes, there are irregular spots like in a crazy patch quilt. 

 Such inflorescences are quite favorable objects for the study of 

 the influence of contiguous tissues with male and female states, 

 especially if the two tissues involve parts of the same flower. 

 The flowers of Arisaema have very deflnite positions in spirals, 

 determined by the fundamental heredity, and it frequently 

 happens that the transition line or zone between two tissues of 

 opposite sexual state passes directly thru a flower, in which 

 case the structure is carpellate on one side and staminate on the 

 other. The incept of the flower is organized as a unit in spite of 

 the fact that the cells on the one side are in a female state 

 and on the other in a male state or at least in a condition leading 

 to these states. The hereditary factors which determine the 

 .position and unity of the flower have no direct relation to the 

 extent or limits of the sexual states. Sometimes, there is an 

 appreciable neutral zone between the typical staminate and 

 carpellate areas, in which case any flower that falls largely or 

 entirely within this neutral strip will be vestigial or develop as 

 an abnormal vegetative structure. 



