94 THE PLANT LIFE OF MARYLAND 



line," the bounds of species which history and climate brings near 

 the line, will there coincide with it, while in other parts of the range 

 of the plant, where its history has been different or the. climate now 

 differs, it may be able to override quite as distinct a line of edaphic 

 demarcation. 



Several of the species confined to the Coastal Zone may be found 

 in cultivation in the Midland Zone. The writer has noticed Mar/iioHa 

 virginiana and Tecoma radicans at Cumberland, and Lonicera sem- 

 pervirens near Midlothian, Allegany County. Ilex opaca, too, while 

 never found as a tree in the Midland Zone, occurs as a rare shrub. 

 These facts indicate that there is nothing in the slightly more rigorous 

 climatic conditions of the Midland Zone to exclude the species named, 

 and point to the cause of the limitation of their present migration as 

 being uncongenial soil conditions or the competition of plants more 

 accurately adjusted to these soil conditions. 



I '.I BLIOGEAPHY. 



Aikix, William E. A., M. D.. Catalogue of Phenogamous Plants and Ferns, 

 native or naturalized, growing in the vicinity of Baltimore, Maryland. 

 Transactions of the Maryland Academy of Sciences and Literature. Vol. 

 I, pp. 55-91, Baltimore, 1837. 

 Lists 1063 species. 

 Barton, Bollino W., M. D. Botanical Conditions in Western Maryland. 

 The New Pedagogue. Vol. I. pp. 99-101, Baltimore, 1899. 

 A popular account of a visit to Garrett County. 

 Bbereton, J. A., M. D. Prodromus of the Flora Columbiana, pp. 86. Wash- 

 ington, 1830. 

 Arranged on the Linnean System. 

 Caxuy. William M. Notes of Botanical Visits to the Lower part of Dela- 

 ware and the Eastern Shore of Maryland. Proceedings of the Academy 

 of Sciences, Philadelphia, 1864, pp. 16-19. 

 Notes on 11 species new to Maryland. 

 CiiicKLiiiNG, J. W., Jr. A Season's Botanizing. Field and Forest, Vol. III., 

 pp. 151-155, 1878. 



Relates in part to a visit to Salisbury and Ocean City, mentioning 

 over 20 species which are uncommon or new to the State. 

 Clark, Hubert Lyman. Notes on Maryland Plants. Rhodora, Vol. VI., pp. 

 176-177. 1904. 



Notes on plants observed in 1903 in the vicinity of Easton and between 

 Berlin and Ocean City. Reports four extensions of range. 



