562 rei-oht— 1884. 



elliottia ; shortia (the curious history of which I need not rehearse) ; 

 styrax of cognate species ; nyssa, the Asiatic representatives of which 

 affect a warmer region ; gelsemium, which under the name of jessamine 

 is the vernal pride of the southern Atlantic States ; pyrularia and. buckleya, 

 peculiar santalaceous shrubs ; sassafras and benzoines of the laurel family ; 

 planera and maclura ; pachysandra of the box tribe ; the great develop- 

 ment of the juglandacea? (of which the sole representative in Europe 

 probably was brought by man into south-eastern Europe in pre-historic 

 times) ; our hemlock-spruces, arbor-vitas, chamaacyparis, taxodium and 

 torreya, with their east Asian counterparts, the roxburghiaceas, represented 

 by croomia — and I might much further extend and particularise the 

 enumeration — you will have enough to make it clear that the peculiarities 

 of the one flora are the peculiarities of the other, and that the two are in 

 striking contrast with the flora of Europe. 



This contrast is susceptible of explanation. I have ventured to regard 

 the two antipodal floras thus compared as the favoured heirs of the ante- 

 glacial high northern flora, or rather as the heirs who have retained most 

 of their inheritance. For inasmuch as the present arctic flora is essentially 

 the same round the world, and the tertiary fossil plants entombed in the 

 strata beneath are also largely identical in all the longitudes, we may well 

 infer that the ancestors of the present northern temperate plants were as 

 widely distributed throughout their northern home. In their enforced 

 migration southward geographical configuration and climatic differences 

 would begin to operate. Perhaps the way into Europe was less open 

 than into the lower latitudes of America and eastern Asia, although there 

 is reason to think that Greenland was joined to Scandinavia. However 

 that be, we know that Europe was fairly well furnished with many of the 

 vegetable types that are now absent, possibly with most of them. Those 

 that have been recognised are mainly trees and shrubs, which somehow 

 take most readily to fossilization, but the hei'baceous vegetation probably 

 accompanied the arboreal. At any rate, Europe then possessed torreyas 

 and gingkos, taxodium and glyptostrobus, libocedrus, pines of our five- 

 leaved type, as well as the analogues of other American forms, several 

 species of juglans answering to the American forms, and the now pecu- 

 liarly American genus carya, oaks of the American types, myricas of the 

 two American types, one or two planer-trees, species of populus answering 

 to our cotton- woods and our balsam-poplar, a sasafras and the analogues 

 of our persea and benzoin, a catalpa, magnolias and a liriodendron, 

 maples answering to ours, and also a negundo, and such peculiarly 

 American leguminous genera as the locust, honey locust, and gymno- 

 cladus. To understand how Europe came to lose these elements of her 

 flora, and Atlantic North America to retain them, we must recall the 

 poverty of Europe in native forest trees, to which I have already alluded, 

 A few years ago, in an article on this subject, I drew up a sketch of the 

 relative richness of Europe, Atlantic North America, Pacific North 

 America, and the eastern side of temperate Asia in genera and species of 

 forest trees. 1 In that sketch, as I am now convinced, the European 

 forest elements were somewhat underrated. I allowed only 33 genera 

 and 85 species, while to our Atlantic American forest were assigned 66 

 genera and 155 species. I find from Nyman's ' Conspectus ' that there are 

 trees on the southern and eastern borders of Europe which I had omitted, 



1 A mer. Journ. Sci., III. xvi. 85. 



