Section IV., 1884. [ IS ] Trans. Roy. Soo. Canada. 



III. — Revision of the Canadian Ranimculaceœ. 



By G-EORGE Lawson, Ph. D., LL.D., Dalhousie College, Halifax, Nova Scotia. 



(Read May 23, 1884.) 



In the year 1870, my monograph of the " Rauuuculaceœ of the Dominion of Canada" 

 was published in the Transactions of the Nova Scotian Institute of Natural Science. Its 

 objects vrere : to show what species of Ranunculaceous plants had been identified as 

 Canadian ; to correct their nomenclature, as far as this could be done with the limited 

 material to which access could then be had ; to present concise descriptions of the species ; 

 to point out their geographical range as then ascertained ; to place on record their 

 local occurrence so far as had been observed ; and, finally, to suggest points for investigation 

 in regard to those species that appeared to be of doubtful rank, whose relations to others 

 were imperfectly understood, or whose occurrence and distribution were imperfectly 

 known. After a lapse of thirteen years, during which period a good deal of botanizing 

 has been done in Canada, and many useful publications bearing upon the North American 

 flora have appeared, — some within our own borders, others in the United States of 

 America, in England, and in Russia, — -I have thought it might be useful to return to this 

 Order, and present to Canadian botanists, through the Royal Society, a fuller and more 

 accurate description of our Ranuuculaceous plants than was possible at the time when my 

 previous paper was prepared. Throughoirt the Dominion many collectors have been at 

 work. In the older provinces, resident amateur botanists and students have, by individual 

 effort and through "field clubs" and similar organizations, already done much good 

 service to science, both in collecting materials and working -a\y the botany of their 

 respective districts. By the rapid opening up of the great Northwest, by the survey 

 explorations over the Plains, among the Rocky Mountains, the Cascades, in British 

 Columbia, and along the Pacific coast, our knowledge of the distribution of our indigenous 

 plants has been greatly extended. The names of those to whom I am indebted for speci- 

 mens, seeds, or information, used in the present paper, will be found under the several 

 species, but foremost among recent collectors may be mentioned the name of Professor 

 Macoun, who, with other officers of the Canadian Survey, has had opportunities such 

 as fall to the lot of few botanists, and, availing himself of them to the fullest extent, he has 

 reaped an abundant harvest, as is shown by the lists already published and by the accu- 

 mulations of material still awaiting examination. I have to express my obligations to 

 Dr. Selwyn, the director of the Survey, for affording me every facility for examinino- 

 the herbaria in the museum. 



It is hoped, by arrajiging the materials of our Canadian collectors and observers, and 

 collocating the results obtained by botanists in other countries, in occasional monographs 



