TRANSACTIONS 



OF THE 



jBtow J&oftaw institute of Natural $tmtt. 



Art. I. — Notes on Nova Scotia Composite, — Asters. By J. 

 Sommers, M.D., Prof. Physiology, Halifax Medical 



College. 



(Read before the Institate, November 13, 1876.) 



The genus Aster being a natural division of the order Com- 

 posite, attracts our attention, because of the beauty and variety of 

 its forms. It is interesting also, because it supplies the botanist 

 with the latest floral treasures which our short season affords for his 

 study and subsequent reflection ; with the golden-rods they light up 

 our autumnal landscape, like a lingering ray of our departed 

 summer. 



The generic characteristics of this group are exceedingly well 

 marked, none others in the whole botanical classification being so 

 separated from their congeners by natural distinctions. 



Their specific diagnosis is, however, exceedingly difficult, as is 

 acknowledged by the diversity of nomenclature and doubtful separ- 

 ations of species, the elevations of varieties into species, and of 

 individuals into varieties, by different authorities, leading to much 

 confusion, so that in many cases, named, species are but examples 

 of a single form, these names being truly synonyms, and not 

 patronymics. An example is here furnished by the form designated 

 Aster lffivis, Linn lasvigatus, "Willd, cyaneus, Hoffm and Pursh 

 described as separate species, now recognized as varieties of an 

 amorphous species, connected by many intermediate variations. 

 Any one of the three may be regarded as the parent stock. Taking 

 the intermediate series we find apparent variations, which, on close 

 examination, fail to establish a well-marked specific distinction. 

 "We are justified, therefore, in designating this form by a specific 



