THE FERN BULLETIN 



*3 



portions and the sporangia also showed every grada- 

 tion of development or rather every stage of degrada- 

 tion and sterilization. In some cases these gradations 

 were shown in all stages on a single leaf and in others 

 the only sign that the leaf had once intended to be fer- 

 tile was the presence of rudiments of the indusia on 

 fully expanded and broad leaves. 



In the summer of 1895 similar experiments were per- 

 formed on the other species O. Struthiopteris and sim- 

 ilar results were obtained. This is the more interesting 

 since to my knowledge no abnormal form of the fruit- 

 ing leaf in this species had been reported, though it 

 would not be surprising if we should hear of some who 

 have found them. These abnormal leaves look very cur- 

 ious indeed in the ostrich fern and they do not reach 

 near the size of the sterile leaves while they often do 

 in the case*' of the sensitive fern. 



While these facts are extremely interesting to all 

 who love ferns there are certain problems connected 

 with the more fundamental relation between the fertile 

 and sterile leaves which are of absorbing interest to me, 

 just now, and of which I cannot here speak because it 

 would make this article too long. But I assure any 

 reader of this note that I should be only too glad to re- 

 ceive specimens of any ferns in which these transforma- 

 tions have taken place and if any one should come 

 across similar transformations of the pistils of flowers 

 to partial leaves, the plant would be very welcome to 

 me. Mr. McLouth has I think rightly interpreted the 

 influence of the fire on the Osmnnda cinnamomca but 

 from some preliminary experiments which I started on 

 this same fern last year, I should think the fire ran over 

 the ground the season prior to the appearance of the 

 abnormal leaves instead of the same season ; but until I 



