A new Botrychium from Jamaica'^ 



William Ralph Maxon 



(With plate 6) 



The systematic status of the members of the group o{ Botrych' 

 imn ternattim has been the subject of a good deal of comment 

 within the past ten years. Naturally there have developed legiti- 

 mate differences of individual judgment and interpretation: and, 

 while in one or two instances the results offered have been such 

 as to suggest doubt that the author was in actual possession of 

 some of the forms under discussion, it is probably true that no two 

 students working with the same series of specimens would arrive 

 at conclusions absolutely identical. It becomes often an exceed- 

 ingly difficult matter to decide whether a given series of plants — 

 and too often a small series — constitutes a sufficiently marked 

 and coherent assemblage to stand apart, specifically distinct, from 

 an obviously related form ; or, whether, on the other hand, it is 

 to be regarded as a mere local variation induced, it may be, by 

 habitat. 



Of the so-called species recently recognized,t several — and 

 they are, in the opinion of the writer, very few in number — do 

 not appear to be valid species in the ordinary sense of the term : 

 they lack distinctive diagnostic characters and pass insensibly into 

 another form. And, it must be confessed, a study of the entire 

 group must of necessity be more truly comparative and involve a 

 wider view than is usually to be required in most groups of pteri- 

 dophytes. But the fact remains, that there are distinct groups, 

 mhabiting definitely restricted areas and comprising individuals in 

 close agreement in habital and foliage characters, which offer com- 

 paratively small but absolute differences from allied groups of indi- 

 viduals from other regions ; and it appears to the writer that, 

 unless reduction of the most sweeping sort is to be made, it is 



* Published by permission of tlie Secretary of the Smithsonian Institution, 

 t Underwood, An index to the described species of Botrychium, Bull, Torrey 

 Club 30 ; 42-55. Ja 1903. 



219 



