CLASSIFICATION AND NOMENCLATURE. 49 



I 26. — Still more complicateci is the ostrich-fern. Its syno- 

 nymy is as follows : 



Osmunda strttthiopteris L., 1753. 



Onoclea struthiopteris Hoffm., 1795. 



Osmunda nodulosa Michx., 1803. 



Struthiopteris Germanica Willd.,* 1809. 



Struthiopteris Pennsylvanica Willd., 1810. 



Matieuccia struthiopteris Todaro, 1866. 



Struthiopteris Germanica var. Pennsylvanica Lawson, 1889. 



Now this case involves several independent problems that 

 are not mere " battles with synonyms " : (i) Is the American spe- 

 cies the same as the European } (2) Are we to take a superficial 

 resemblance like the rolling of the sporophyll into a necklace- 

 shaped structure as a basis for comparison, and unite a species 

 with leaves growing in crowns from an upright rootstock and 

 having free veins, in the same genus (^Onoclea) with a plant that 

 has horizontal creeping stems, scattered leaves, and copiously 

 anastomosing veins ? These are problems on which human 

 judgment will disagree as it has disagreed in the past. In regard 

 to the latter question the practice of the Kew botanists followed 

 too implicitly by us Americans was adopted in previous editions 

 not without many misgivings. We believe that the two ferns 

 form two as valid generic groups as exist ; that there is nothing 

 in common between them to indicate community of origin or 

 even anything but the most distant relationship. They are 

 therefore treated in this edition as two genera. In regard to the 

 question of the identity of the European and American plants, 

 we will say that, having been familiar with our American species 

 from childhood, and having studied the European form in its 

 native soil, we are forced to the conviction that there is but one 

 species on the two continents. If this be the case, whatever the 

 generic name may be, the specific name of our species must be 

 Struthiopteris, the Linnaean specific name for the plant. 



If we adopt the view that the American plant is distinct 

 from the European, our plant would then bear the specific name 



* Applied to the American plant by various authors, but Hmited by Will- 

 denow to the European plant. 



