664 PROCEEDINGS OF THE ACADEMY OF [Oct., 



With regard to geographic distribution of the forms of violets, both 

 caulescent and acaulescent, that I have identified in eastern Pennsyl- 

 vania and southern New Jersey, six are characteristic boreal species, 

 being found abundantly in the highest mountain districts, where the 

 fauna is decidedly Canadian. Of these V. canadensis, V. selhirki, V. 

 renifolia are restricted to this region, but V. rostrata, V. leconteana 

 and V. roundifolia extend much farther south in suitable locations, 

 the last two reaching the southeastern corner of Pennsylvania. V. 

 muhlenhergii, V. cucullata and V. scabriuscula also occur in the higher 

 Alleghanies, but are equally as plentiful about Philadelphia. 



Another group of species seems to be decidedly southern, and is 

 limited to the low grounds of the lower Delaware and Susquehanna 

 valleys or the coastal region of New Jersey, in the Carolinian faunal 

 belt, viz., V. hrittoniana, V. lanceolata, V. septemloha and V. rafinesquii. 



The other forms, including the various forms of V. palmata and fim- 

 hriattda, seem to range indiscriminately over the intervening country, 

 most of them spreading over the habitat of the last group as well. 



The Violets of Philadelphia and Vicinity. 



The following synopsis is the result of several years' study, during 

 which time a series of several thousand specimens has been collected 

 and preserved and many observations upon living plants recorded. 

 Undoubtedly further investigations will detect additional forms, and 

 this list is not claimed to be complete but rather a basis for future 

 work, in the belief that local studies of the genus will aid us in 

 eventually gaining a better understanding of its species. 



In the identification of the species I have to express my deep in- 

 debtedness to Prof. Edward L. Greene, the leading authority on the 

 genus, who very kindly examined a series of my specimens and gave 

 me his views upon their relationship, and also to Mr. Charles Louis 

 Pollard, who has from time to time identified specimens for me. 

 The types of Nuttall, Schweinitz and Muhlenberg in the herbarium of 

 the Academy have thrown much light on the application of some 

 of the older names. 



We may consider the species in two main groups : 



I. Acaulescent species, leaf petioles and flower scapes both arising 

 from the root-stalk (p. 665). 



II. Caulescent species, with a leafy stem upon which the flowers are 

 produced (p. 686). 



