2 ROCHESTER ACADEMY OF SCIENCE. [Oct. 8, 



Introduction of Species 12 



Disappearance of Species 12 



Forest Trees 13 



Statistics of the Flora 14 



Systematic Distribution 14 



Leading Orders ^ 14 



Leading Genera 15 



Comparative Statistics 16 



Affinities of the Monroe Flora 17 



General Comparison 17 



Comparison with the Cayuga Flora 19 



Plants common to the Monroe and Cayuga Floras 19 



Comparison with the Buffalo Flora 20 



Plants common to the Monroe and Buffalo Floras 20 



Comparison of Cayuga and Buffalo Floras 22 



Plants common to the Cayuga and Buffalo Floras 22 



Lists of Plants peculiar to each of the three Floras .... 22 



Plants peculiar to the Monroe Flora 22 



Plants peculiar to the Cayuga Flora 24 



Plants peculiar to the Buffalo Flora 26 



Physical Characters of the Region, by H. L. Fairchild 28 



Geography and Hydrography. 28 



Topography and Altitudes. . . 28 



List of Elevations ... 29 



Geology 31 



Stratigraphy 31 



Pleistocene Drift 33 



Influence upon Plant-life 35 



Climatic Conditions 36 



Statistics of Climate at Rochester 36 



Date of earliest blossoming of Trees 38 



The Catalogue .... . .. . 39 



Explanation of Plan 39 



Authorities 39 



Typography and Reference Marks 40 



List of Phanerogams 41 



List of Vascular Acrogens 131 



Bibliography 135 



Corrections and Insertions 146 



Index to Orders and Genera 147 



Inception of the Work ; Authorship. 



The Botanical Section of the Rochester Academy of Science has 

 for many years entertained the plan of eventually publishing the 

 flora of this region, and the members of the Section have individually 

 and collectively labored earnestly toward that end. About four years 

 ago the Section appointed a Committee, consisting of the Chairman 

 and Vice-Chairman, to compile and prepare for publication the flora 

 of Monroe county and adjacent territory. The Committee have 

 collated all the lists of plants of this vicinity which they have been 

 able to obtain, have examined the specimens in the herbarium of the 

 Academy, and have used all available sources of information. 



