Hill: Penobscot Plants. 287 



Thalictrum polygamuin Scutellaria galericuhita 



Lathyi'us palustris, Galiiun trifidum 



var. pilosus Mentha arvensis 



Alleghanian Element 



The second of these phytogeographical regions — the eastern 

 deciduous or Alleghanian forest — has its center of distribu- 

 tion in the Ohio Vallev and the southern Appalachians. 

 This Alleghanian zone proper does not extend far into Xew 

 England, but under favorable environmental conditions cer- 

 tain of its species have been able to exceed the general limits 

 and advance northward to eastern Maine and the Maritime 

 Provinces, and in some cases even to Newfoundland. Only 

 those species which extend to Cape Breton or Newfoundland 

 are included in this group. Typical examples include: 



Pinus Strobus Betula luiea 



Smilacina racemosa Far/us (jrandifuUa 



Medeola virginiana Acer rubrum 



Trillium undidatum Prunus virginiana- 



A detailed discussion of this element of the Canadian- 

 Alleghanian flora will be taken up in connection with the 

 more strictly Alleghanian plants in Group IV. 



Group IV. Alleghanian Plants 

 In contrast to the species of the two previous groups, which 

 represent for the most part a boreal flora approaching its 

 southern limits, there exists in the eastern Penobscot Bay 

 region another group which represents an austral flora at the 

 northern limits of its range. This group of 56 species, 9 

 per cent of the flora, consists of plants which have a wide 

 range to the southwest but northward reach only to eastern 

 New England and adjacent Canada. 



