THE FERN BULLETIN 



si 



by the sun's heat; not "especially near waterfalls" as 

 Gray's Manual says. Look for a place where there is 

 a bare cliff, overhanging- a little, perhaps, so that the 

 rain cannot reach it and up above all the trees so that it 

 can have no shade at all and if you find a fern there 

 test it by its perfume, its stickness and its beautiful 

 brown curls. — James A. Bates, in Linneacn Fern Bul- 

 letin, Vol. IV., p. 3. 



THE RELATION BETWEEN THE STERILE AND 

 FERTILE LEAVES OF DIMORPHIC FERNS. 



The dimorphism existing between the leaves of cer- 

 tain ferns which have expanded sterile leaves and 

 smaller ones devoted entirely to the production of 

 spores, presents in some species very interesting prob- 

 lems which, have hitherto received but little attention. 

 This note to the Linnaeau Fern Bulletin is suggested 

 by the note on Osiniiuda cinnamomea frondosa in the 

 January number by Air. C. D. McLouth. That note is 

 a very interesting one to me, since I have been engaged 

 for two years with experiments on two other dimorphic 

 ferns belonging to the genus Onoclea viz., 0. sensibilis 

 and O. Struthiopteris, both of which grow in abund- 

 ance near Ithaca. Readers of the Bulletin will recollect 

 a form of the sensative fern which was named by Dr. 

 Torrey, O. sensibilis obtusilobata, and which was even 

 described by Schkuhr as 0. obtusilobata. As will be 

 seen by comparing recent editions of Gray's botany this 

 has recently been considered by some as simply an ab- 

 normal form. 



At the Rochester meeting of the A. A. A. S. Prof. 

 L nderwood presented a note on the form of this fern 

 and suggested that the intermediate fruiting leaf was 

 the result of some injury to the sterile leaf. This was 



