20 American Fern Journal 



areolae of the leaves of a given species always vary in- 

 versely in size with the age of the tree, a fact of very con- 

 siderable interest and importance will have been estab- 

 lished. 



Fern students should give this hypothesis a thorough 

 test. Anyone can do this provided sufficient care is taken. 

 The only requisites are carefulness, time and diligence. 

 Reports of such studies will be gladly received for publi- 

 cation in the Journal. 



In order to test the hypothesis in the case of any par- 

 ticular kind of fern, the first thing to be done will be to 

 obtain plants showing a considerable range in age. This 

 will need great care, as it is not always easy to tell whether 

 a small plant is a sporeling or stem offshoot from another 

 plant, With the proper material selected, the next step 

 would be the measurement of the spaces between veinlets 

 to determine whether they are constantly different in 

 size in plants of different ages. In order to get results 

 which would be at all conclusive, it would be necessary 

 to examine a large amount of material. Onoclea sensi- 

 bilis suggests itself as obviously the best adapted of our 

 common temperate ferns, but it would be worth while 

 applying the theory to the free-veined species as well. 



R. C. B. 



American 



Photographs of ferns and of fern students always make 



and 



to receive any such as may be sent in, especially if accom- 

 panied by a contribution toward the expense of reproduc- 

 tion. A full page haif-tone plate costs about three dollars ; 

 smaller cuts at proportionate rates. It is hoped that at 

 least two such plates may be printed each number. 



