Jennings : A Botanical Survey of Presque Isle. 355 



The Sabbatia-Linuvi Formation. 



Supplanting the upper part of \\\e funcus-Eleocharis formation, and, 

 more especially, the Carex Oederi ptunila society, is a formation, 

 which, unlike any of the formations before described, consists mainly 

 of rosette -forming biennials and perennials. 



The structure of the formation is, typically : 



Fades. — 



Sabbatia angularis, Liniim tnedium. 



Principal Species. — 



Gerardia paupercula, Ibidium inciirvum, 

 . Lobelia Kalmii. 

 Secondary Species. — 



Utricularia cornuta, /uncus tetiuis, 



Eleocharis obtusa, Scleria verticillala, 



/uncus canadensis, Campanula aparinoides, 



Nostoc sp., Psilocybe aminophila. 



This formation is practically a closed one, but aside from sev- 

 eral quite distinct aspects there is practically no grouping, the 

 species being indiscriminately intermingled within the limits of the 

 habitat. This formation more proportionally than any other forma- 

 tion on the peninsula is marked by the variety and abundance of its 

 floral display, the different species alternating with each other in their 

 periods of bloom to such an extent that flowers are in evidence almost 

 continuously from early summer till late fall. 



Some of the more important species characterizing corresponding 

 aspects are : 



Sabbatia angularis, Linum medium. 



Lobelia Kalmii, Gerardia paupercula, 



Lbidium incurvum Utricularia cornuta. 



The Populus-Salix Formation. 



This formation in the stage under discussion usually occupies a 

 habitat now completely on a level with the surrounding sand-plain, 

 and indeed very little different from that habitat in most particulars. 

 Around Lagoon D the cottonwoods have attained to a diameter of 

 three and one-half inches and are beginning to lose some of the lower 

 branches. The willows are beginning to die out also, so that the 



