26 The Ohio Journal of Science [Vol. XX, No. 2, 



carpels are not distributed in any definite way on the bispor- 

 angiate flowers of intermediate individuals. In a staminate 

 flower, for example, a single carpel mayappear in the 

 outermost part next the sepals. The same is true of flowers 

 that have a larger number of carpels. The carpels may 

 occupy any chance position on the floral axis. The same 

 conditions apply to stamens in carpellate flowers. A study of 

 the bisporangiate species of Thalictrum shows that the ancestral 

 type had the normal central or terminal carpels and lateral 

 stamens as intimated above. 



Below is a record of a few plants showing the number and 

 character of the opposite kinds of sporophylls in staminate and 

 carpellate individuals which show some degree of intermediate- 

 ness. As stated, any degree of staminateness or carpellateness 

 from either extreme to typical intermediate can be found 

 among the plants growing in the field. 



An individual with pure staminate flowers only. 



A staminate plant having numerous staminate flowers and 1 flower with 

 numerous stamens and a single carpel. 



A staminate plant with 2 bisporangiate flowers, each with a single carpel. 



A staminate individual having 1 bisporangiate flower with 4 carpels. 



A staminate plant with 3 bisporangiate flowers; 1 flower with 5 carpels 

 and 2 flowers with 2 carpels each. 



A staminate plant having 1 bisporangiate flower with 2 carpels and 1 

 with 5 carpels. 



A staminate plant with 3 bisporangiate flowers; 1 with 1 carpel, 1 with 

 2 carpels, and 1 with 4 carpels. 



A staminate plant with 3 bisporangiate flowers; 1 flower with 1 carpel, 



1 flower with 2 carpels, and 1 flower with 5 carpels. 

 A staminate plant with 12 main branches of the inflorescence; 9 branches 

 had all pure staminate flowers; 1 branch had 1 bisporangiate flower 

 with a single carpel, 1 branch had 1 bisporangiate flower with 3 car- 

 pels, and 1 branch had 1 bisporangiate flower with 7 carpels. 



A staminate plant with 7 bisporangiate flowers; 3 flowers with 1 carpel 

 each, 1 flower with 2 carpels, and 3 flowers with 5 carpels each. 



A staminate plant with 17 bisporangiate flowers, each of those flowers 

 having from 1 to 5 carpels. 



A staminate plant having 33 bisporangiate flowers, the carpels in each 

 flower ranging from 1 to 13. 



A staminate plant with 37 bisporangiate flowers, the number of carpels 

 in a flower ranging from 1 to 12. 



A plant having about an equal number of staminate and pure carpellate or 

 bisporangiate flowers. Some bisporangiate flowers had but one stamen 

 and some but one carpel, others ranged in degree from such a condition 

 to flowers with about an equal number of stamens and carpels. 



A carpellate plant with 9 bisporangiate flowers; 4 flowers with 1 stamen 

 each, 3 flowers with 2 stamens each; and 2 flowers with 3 stamens each. 



A carpellate plant with 8 bisporangiate flowers; 6 flowers with 1 stamen 

 each and 2 flowers with 2 stamens each. 



A carpellate plant with 5 bisporangiate flowers; 3 flowers with 1 stamen 

 each, 1 flower with 2 stamens and 1 flower with 3 stamens. 



