KARK LOCAL FRRNS. 45 



certainty on this head. Indeed, the whole question is by no 

 means simple. Fertility in hybrids, whether natural or artifi- 

 cial, is an exceedingly variable quantity, as we have reason to 

 know. Apparent sterility may often be something else, as for 

 instance the unpreparedness of a new organism to meet all the 

 many environmental influences that have been met and con- 

 quered, one by one, by those forms that have, by virtue of this 

 warfare of theirs, become the valiant survivors of the struggle 

 of the centuries. Long experience, and hard knocks, have 

 made them what they are. Every new form, whether a varia- 

 tion or a hybrid, must take the knocks, and do the best it can 

 in the absence of experience. The outcome depends upon 

 whether or not it can do well enough. 



It is quite conceivable that A. ebeyioides is a fertile hybrid, 

 and in view of the Havana Glen situation, when this is taken 

 with the other facts, such is the probable inference. For it 

 must not be forgotten that the plant is rare ; that it occurs 

 always, so far as known, in company with its supposed par- 

 ents ; that its characters are intermediate. Above all, it must 

 be remembered that Miss Slosson has produced a hybrid form, 

 apparenth'- identical with the naturally occuring A. ebenoides, 

 by placing in juxtaposition the archegonial parts of one, and 

 the antheridial parts of the other, of these companion species. 

 (Whether this artificial hybrid has proven fertile is not known 

 to the present writer). Now it is quite possible that the 

 cryptic conditions which elsewhere work against the survival 

 of the hybrid, if it is a hybrid, are in abeyance at Havana 

 Glen ; and that the plant is there able to continue itself indef- 

 initely. It is thinkable, indeed, that in the course of many 

 generations the fern may gain such stability and stamina at 

 that place as to be able to spread abroad and survive elsewhere. 



Meantime, as has been said, the fern is of a pronounced 

 rarity. So seldom is it met with that students and collectors 

 in all parts of the co:intry are chronically in want of speci- 

 mens. All lovers of ferns, especially, are looking for it in all 

 probable places. To p.nnounce its discovery is to receive from 



