19 



Botany that only mere mention of them is necessary here. C'on- 

 versely, WiUis* has argued that the endemic element in the flora 

 of Ceylon is a criterion of its youth. He says, in fact, that the 

 endemic element in the Ceylon flora is the youngest. Is one, 

 or the other, or both, of these diametrically opposed statements 

 to be discarded? Or is endemism in a flora a matter with which 

 antiquity or youth has little or nothing to do? An answer to 

 these questions seems to be furnished by the behavior of the 

 endemics in the local region. A middle course, a compromise if 

 you will, between the champions of youth and age may be not 

 only "playing it safe," but true. 



One of the points made by Bailey and Sinnott is, that on the 

 whole, endemic species are not only the most ancient element in 

 any given flora, but that they are also more apt to be of a woody 

 than an herbaceous type. They came to this conclusion after 

 an elaborate study of the problem from many angles, one of 

 which was phytogeographic. Furthermore their contention is 

 that of the endemic species in a flora, the species of the endemic 

 genera would be still greater criteria of antiquity and still more 

 apt to be woody. The facts, as illustrated in our region scarcely 

 support either of these opinions. In the total flora of the 

 vicinity of New York 83 per cent, of the vegetation is herbaceous! 

 and 17 per cent, woody. Of the 22 endemic species only four, 

 Prunus Gravesii, P. alleghaniensis, Salix sgiiamata, and Dendrium 

 huxifolium, are woody, which is 18.18 per cent, of the total 

 endemic element. The percentages of woody plants among the 

 endemics and among the total flora, are too nearly alike to 

 support the theory that the endemic element of a flora is pre- 

 dominately woody, for in our area it is no more or less so than 

 1.2 per cent, which means nothing. In other words, the woody 

 and herbaceous elements of the total vegetation bear essentially 

 the same ratio, one to the other, that we find among the purely 

 endemic species. 



As to the antiquity of the endemic element in our native flora 



* Willis, J. C. The endemic flora of Ceylon with reference to geographical 

 distribution and evolution in general. Phil. Trans. Royal Soc. London B. 206: 

 307-342. 1914. 



t Am. Jour. Bot. 2: 23-31. 1915. 



