Spore abortion rate was studied for a total of 109 samples belonging to 23 fern taxa. The resulting abortion rate was compared within several reproductive and phylogenetic groups. The method of spore abortion estimation was optimized by analyzing the amount of spores needed as well as the potential differences within frond.

This thesis has examined a long existing conflict between two ferns, Asplenium platyneuron and Athyrium pycnocarpon. The study included habitat, external and internal morphological characteristics, and biochemical analyses of the free amino acids. Major emphasis was placed upon vascular structure and arrangement in the stipes, roots, and rhizomes.Biochemically, the free amino acids were separated by one-dimensional descending paper chromatography. All areas investigated were either photographed or drawn and presented in the text of the thesis.Ball State UniversityMuncie, IN 47306