34 THE AMERICAN BOTANIST 



The Ancikxt Fi^ORA. — Those unfamiliar with the early 

 history of the American flora may have the impression that the 

 plants we now see about us are the descendants of those which 

 hrst lived in tlie locality and resemble them in general appear- 

 ance, but nothing could be further from the facts. The flovver- 

 mg plants, especially, seem to l)e rather recent comers on our 

 l)lanet, comparatively speaking. There were perhaps millions 

 ot years during which the vegetation contained no example of 

 a plant witli flowers. Apparently mosses, algae, ferns and 

 smiilar plants were much earlier. Since plants first began to 

 be. great changes have taken place in the surface of the earth 

 and there have been correspondingly great changes in the plant 

 covering. The ages just preceding the present were particu- 

 larly charactrized by such changes, and Edward W. Ik-rrv 

 writes of them as follows: "During the upper lv)cene and 

 lower Oligocene the climate of our Gulf tier of States and 

 soutliern iCurope became strictly tropical ant! the region was 

 overrun by an appropriate tropical \egetation while the tem- 

 perate forests pushed int(. the polar regions until most if not 

 all the lands within the Arctic Circle and i)art at least of tlie 

 •Antarctic continent were forested 1)y cool temperature plants. 

 The most extensive of these polar floras is tliat recordetl from 

 western Greenlan<l (latitude ??> ) wliich included nearly 300 

 different species, h'ighteen of these are ferns. 28 are conifers 

 including the ginkgo, incense cedar, express, and numerous 

 >e(|uoias and ])ines; 21 are niouocotyls including two pahns; 

 and a vast abundance of dicotyledonous leaves of willow, pop- 

 lar, alder ha/.el. beech, oak. elm. sycamore, walnut, ash. service- 

 berry, sumacli. dogwood, gum. grape, magnolia. ni;iple, bollv. 

 buckthorn, hawthorn, etc. Traces of this flora :ire found in 

 Grinnell T.and, Spitsbergen, Iceland. Siberia, and elsewhere to 

 within <S or 10" ,,f the North Pole in a region that has since 

 become a desert of snow and ice. In the southern United 



