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more slender, diffuse, and pliant habit. The principal distinc- 

 tion, however, is the thin, soft hair which clothes it all over ; 

 while abortivus is invariably smooth. The micranthus grows at 

 Melrose in dense tufts, of a dozen or fifteen stems with inter- 

 laced, fibrous roots, but entirely distinct. The stems branch 

 more commonly from the base than in abortivus, which is apt to 

 send up a single stem, branching above. The smaller specimens 

 of abortivus most nearly resemble micranthus, though the leaves 

 are then apt to be all entire. 



The occurrence of this species in such abundance in one little 

 spot on our Atlantic border, the only locality known, except the 

 Lake Superior one, east of the Mississippi, is very interesting. It 

 suggests the idea that, after all, the micranthus may be merely a 

 variety of abortivus^ which is common all over the country, de- 

 veloping itself more extensively at the West. The points in which 

 they differ are certainly those in which plants are most likely to 

 vary. The division of leaves is by no means a certain specific 

 difference. No characteristic is more variable. The outer cover- 

 ing of plants varies exceedingly with soil and exposure ; so much 

 so, that many varieties, now included under one species, were 

 originally described as distinct on this account. The Lake Supe- 

 rior specimen of this Ranunculus is intermediate in this respect, 

 having but little hair, and also entire leaves, with the lobate ser- 

 ratures peculiar to micranthus. The only thing which gives 

 particular weight to this covering, as a specific, character, in this 

 instance, is that the Melrose plants grow in just that locality 

 "which would cause its disappearance rather than its growth. Mr. 

 Nuttall says : " distinguished from JR. abortivus^ which it much 

 resembles, by the constant hairiness of the stem, calyx, and 

 petioles, as well as by the very different form of the primary 

 leaves." The hairiness does certainly exist as a distinction, but 

 certain leaves of abortivus are as deeply cut as those of mz- 

 cranthus ; and so far as outline goes, these might constantly be 

 exchanged without altering to the eye the general appearance of 

 the plants. I should wish to examine a greater number of speci- 

 mens from different localities, to decide conclusively whether or 

 not they are radically distinct species. At any rate, they ap- 

 proach each other so nearly in certain forms, as to require 

 careful examination. 



