44 



acters, and, second, such varied combinations of these 

 characters as to indicate strongly that intercrossing 

 of the species has occurred, and that repeatedly. 



Typical D. diphylla , D» laciniata , and P. maxima 

 ha^ been found repeatedly - the first two in considerable 

 abundance, while the third can hardly be said to be 

 "scarce" at present in the Oayuga flora. Besides these, 

 and growing in close association with them, have been 

 found a remarkable series of yariant forms -some fairly 

 referable to one of these 3 species, others more uncert- 

 ain in their relationship. 



It may be said at once that D. heterophylla prob- 

 ably does not occur here, there are left the two sup- 

 posedly local forms of Gray's Manual, p. inolsifolia 

 and D. anomala , the latter admittedly a possible hybrid. 

 Some of the peculiar forms of the Oayuga flora could prob- 

 ably very well be referred to the first of these types, 

 and perhaps some to the second. The range of variation 

 is such, however, that the attempt to refer all of the 

 specimens to the 6 species -types then available would 

 seem to necessitate the drawing of arbitrary lines be- 

 tween the species, or else the making of the classifi- 

 cation according to the preponderance of characters. 

 Either process would be sufficiently formed and mechan- 



