560 report— 1884. 



genera and not far from ninety species. All Europe has only seventeen 

 genera and barely fifty species. We have most of the actual European 

 species, excepting their rhododendrons and their heaths, — and even the 

 latter are represented by some scattered patches of calluna, of which it may 

 be still doubtful whether they are chance introductions or sparse and scanty 

 survivals ; and besides we have a wealth of peculiar genera and species. 

 Among them the most notable in an ornamental point of view are the 

 rhododendrons, azaleas, kalmias, andromedas, and clethras ; in botanical 

 interest, the endemic Monotropese, of which there is only one species in 

 Europe, but seven genera in Nortb America, all but one absolutely 

 peculiar; and in edible as well as botanical interest, the unexampled de- 

 velopment and diversification of the genus vaccinium (along with the 

 allied American type, gaylussacia) will attract attention. It is interesting 

 to note the rapid falling away of ericaceaa westward in the valley of the 

 Mississippi as the forest thins out. 



3. The wealth of this flora in composite is a most obvious feature ; 

 one especially prominent at this season of the year, when the open 

 grounds are becoming golden with solidago, and the earlier of the 

 autumnal asters are beginning to blossom. The composite form the 

 largest order of phasnogamous plants in all temperate floras of the northern 

 hemisphere, are well up to the average in Europe, but are nowhere so 

 numerous as in North America, where they form an eighth part of the 

 whole. But the contrast between the compositas of Europe and Atlantic 

 North America is striking. Europe runs to thistles, to inuloidea?, to 

 anthemideos, and to cichoriaceae. It has very few asters and only two 

 solidagos, no sunflowers and hardly anything of that tribe. Our Atlantic 

 flora surpasses all the world in asters and solidagos, as also in sunflowers 

 and their various allies, is rich in eupatoriacea?, of which Europe has 

 extremely few, and is well supplied with vernoniacere and helonioideas of 

 which she has none ; but is scanty in all the groups that predominate in 

 Europe. I may remark that if our larger and most troublesome genera, 

 such as solidago and aster, were treated in our systematic works even in 

 the way that Nyman has treated hieracinm in Europe, the species of 

 these two genera (now numbering 78 and 124 respectively) would be at 

 least doubled. 



4. Perhaps the most interesting contrast between the flora of Europe 

 and that of the eastern border of North America is in the number of 

 generic and even ordinal types here met with which are wholly absent 

 from Europe. Possibly we may distinguish these into two sets of differing 

 history. One will represent a tropical element, more or less transformed, 

 which has probably acquired or been able to hold its position so far north 

 in virtue of high summer temperature. (In this whole survey the penin- 

 sula of Florida is left out of view, regarding its botany as essentially 

 Bahaman and Cuban, with a certain admixture of northern elements.) 

 To the first type I refer such trees and shrubs as asimina, sole represen- 

 tative of the anonacea; out of the tropics, and reaching even to lat. 42° ; 

 chrysobalanns, representing a tropical sub-order; pinckneya representing 

 as far north as Georgia the cinchoneous tribe ; the baccharis of our coast 

 reaching even to New England ; cyrilla and cliftonia, the former actually 

 West Indian ; bumelia, repi'esenting the tropical order sapotaceao ; bignonia 

 and tecoma of the bignoniacete ; forestiera in oleaceae ; pei-sea of the 

 laurineas ; and finally the cactaceos. Among the herbaceous plants of this 

 set, I will allude only to some of peculiar orders. Among them I 



