otes and News 19 



W. A. Poyser, formerly secretary of the Society has 

 been appointed editor-in-chief of "The Aquarium," a 

 monthly published by the Aquarium Societies of Chicago, 

 New York, Philadelphia, Milwaukee, Minneapolis, and 

 Boston. 



Mr. Carl Christensen is now preparing a supplement 

 to his "Index Filicum." In connection with this, he 

 asks to be informed of any errors, or omissions which may 

 have been noted in the "Index." The supplement will 

 include a list of all the new species and new names pro- 

 posed s'nce the "Index" was issued and also corrections 

 of any mistakes which may have been discovered in the 

 original volume. Any one who has know' edge of any 

 detail which needs correction should send it to Mr. 

 Christensen. His preparation of the "Index" has placed 

 fern students forever in his debt. 



Address, Mr. Carl Christensen, Botanical Museum, 



Copenhagen, Denmark. 



Can the age of a fern plant be estimated with any de- 

 gree of accuracy by an examination of its venation? 



The query is suggested by a brief article which appeared 

 in Science during the preceding year and which dealt with 

 the relation of the venation of oak and other leaves to 

 the age of the plant producing them. The writer of the 

 article adduced facts to show that the size of the areolae 

 or vein meshes varied in the plants studied with the age 

 of the trees: the older the tree, the smaller the areolae. 

 This variation he found seemed to hold good not only for 

 the life history of the leaves of a single stem, but also 

 for the leaves of sprouts and trees developed from sprout-. 

 This last fact is most interesting and significant for sprout 

 leaves often appear extra large and in other respects like 

 those of young vigorous seedlings. If it is proved that the 



