Field and Forest. 65 



The Distribution of Certain Species of Aster. 



Notwithstanding the many observations made and recorded respect- 

 ing Topographical Botany, one item has been quite too often neglect- 

 ed, alike in systematic treatises and in reports of scientific surveys. 



That is, special notice of the characteristic species of different 

 localities ; not merely characteristic as found in a given locality, 

 abundantly, or even exclusively, but as found in masses, thus giving 

 character to the landscape, as different species of Erica in the Old 

 World, or as various Cotnposifac, notably the Solidagos often do in the 

 New World. 



These characteristic species may be fruticose, and thus changing 

 but little with the season, except at the time of infloresence, and 

 varying only with the boundaries of their special district. 



Or they may be herbaceous, either annual or perennial, and thus 

 vary not only with the district, but also with the season, as one 

 species passes its infloresence, disappears, and is succeeded by an- 

 other. 



While as regards distribution of some of the most common allied 

 species, they very often replace each other, either gradually, one spec- 

 ies becoming less abundant as the other becomes more so, or else 

 having a sharply dividing line between them, as the result of variation 

 in soil, vicinage to the sea, water-shed, and other conditions. 



The past suiiimer it came in my way to make some observations up- 

 on several Asters sustaining such relations to each other. 



By the last of August or first of September, the fields and woodsides 

 of the Atlantic seaboard are whitened with low bushy Asters ; at first 

 seeming to be similar, and to the last perplexing the observer with all 

 sorts of variations from any well defined normal type. 



Upon examination, however, these may be separated into A. multi- 

 flrus, Ait., A. ericoides, L., A. Tradescanti L. d^ndvar. fragilis. 



In eastern Massachusetts they are mainly of two species. The first 

 of these, Aster multiflorus, is characterized by its small linear leaves ; 

 its crowded heads clustered in cylindrical racemes along the slender, 

 often recurved branches, and its minute hoary pubesence. This 

 species is found all the way from Maine to Virginia, though less 

 abundantly as we go south. 



The other species is A Tradescanti, distinguished by its long linear 



