28 Brown: Apogamy in Phegopteris polypodioides 



cells in thickness, while the other was wider, only one cell in 

 thickness, and with a broad notched apex. Series of short 

 tracheids were formed in both the thickened region of the elonga- 

 ted portion of the sporophyte and on its branch. Another out- 

 growth, prothallus-like in form, developed from the margin 

 of one wing of the prothallium and bore on its margin an antheri- 

 dium. 



Figs. 12-20 



Fig. 15 shows an apogamous outgrowth which developed by 

 the narrowing and lengthening of the apex of a prothallium one 

 cell in thickness. It soon branched, one branch being very 

 irregular in form and only one cell in thickness, while the other 

 was elongated and several cells in thickness in the central 

 region where it bore a group of long tracheids. A small side 

 branch was given off from the apogamous outgrowth. 



