92 



LOWER EOCENK FLORAS OF SOUTHEASTERX NORTH AMFItlCA. 



rated points as Alaska, Ori\<i;(>n. (irccnlaiul, and 

 France. Thoro aro 2 species in the Olij^ocene 

 of Asia and Europe. Nine or ten Miocene spe- 

 cies are present throughout Euro]ie and North 

 America (Xew Jersey to Oregon) and in eastern 

 Asia. Three Phoccne species are found in 

 SpaiiL Franc(\ Italy, Gernumy, Austria, Styria, 

 and Slavonia. Typical fruits preserved in the 

 upper Pliocene (if Germany show how late the 

 genus flourished in central and southern Eu- 

 rope. Felix has described the petrified wood 

 from the Tertiary of Himgary as Liquidam- 

 baroxj-loa. The existing Liquidamhar styrn- 

 ciflua is found in the Pleistocene of West ^'ir- 

 ginia, North Carolina, and Ala])anui, and the 

 eastern Asiatic species L. Jonnofidvd occurs in 

 the Pleistocene of Japan. The genus Cory- 

 lopsis occurs in the post-Miocene deposits of 

 Japan, and its seeds are also found in the 

 Dutch Pliocene. Capsules and seeds of the 

 genus Bucklandia are also present in the 

 Dutch Pliocene. 



The family Rosaceae includes about 90 gen- 

 era and more than 1,300 existing species, widel_y 

 distributed, mostly in temperate regions. Some 

 of the genera like Crataegus seem to be under- 

 going saltation at the present time and hun- 

 dreds of supposed species have been described 

 in the past few years. The tribe Chrysobala- 

 noidere is confined to the Tropics, and the Neu- 

 radoidejc to the subtropics of Africa and 

 southwestern Asia. All the other tribes of Ro- 

 saceae are widely distributed and their modern 

 and fossil distribution is without especial sig- 

 nificance for the present discussion. 



The only genera represented in the Wilcox 

 are Chrysobalanus, which includes species that 

 are evidently the prototypes of the still existing 

 forms, shrubs or small trees, but two or three in 

 number, which iniiabit the sandy shores in the 

 maritime regions of Florida, tropical America, 

 and western tropical Africa, and the stones of 

 a species of Prunus. 



The Leguminosaj, as now segregated into 4 

 families, constitutes the largest alliance among 

 th(! (Tioripetahe (ArchichlamydeaO ami next to 

 the Compositie is the largest angiospermous 

 group. It contains more than 9,000 existing 

 species segregated anrong about ■ii'A) genera. 



There is a wcU-defined floral progression 

 from the family Mimosacea', which has actino- 

 morphic fiowcrs and numerous, mostly free 

 stamens, through the Ctesalpiniaceji^, to tlic 



largest group numerically, tlie l'a])ihonac(ne, 

 which has strongly zygomorphic flowers and 

 coalescent stamens, comparalile with the like 

 culmination in floral evolution of the Orchida- 

 ceje among the Monocotyledonie. 



The Mimosacea\ which includes about 'M 

 genera and 1.400 existing species, is massed in 

 tlie Tropics of both hemispheres. None of the 

 subfamifies are confined to a single continent, 

 but comparatively few genera occur in more 

 than two continental areas and half the genera 

 are restricted to one continent. Asia and Aus- 

 tralia each have '2 peculiar genera, Africa has 4, 

 and America has 7. America also leads in num- 

 ber of species, about half the total number in 

 the family being present in the New World. 

 Australia comes next with more than 300; 

 Africa next, also with more than 300: and Asia 

 last with about 100. In the eastern United 

 States there are only 3 genera and 5 species, 

 none of which are arborescent. In the Gulf 

 States there are 14 genera and 44 species. 



The CiPsalpiniaceie, which includes alxiut 90 

 genera and 1,000 species, is also mainly trop- 

 ical and its forms are massed in the American 

 Tropics, where there are more than 600 species 

 and 37 peculiar genera. The tribe Sclerolo- 

 biea? is entirely American and contains numer- 

 ous monotypic genera. Asia and Africa each 

 have about 150 species. There are, jiowever, 

 only 10 Asiatic genera, as compared with 17 

 African. There are but 3 Australian genera 

 and less than 100 species. In the eastern 

 United States there are 5 genera and 11 spe- 

 cies. Three of the genera, Cercis, Gleditsia, 

 and Gymnocladus are arborescent. In the 

 Southern States there are 11 genera and 44 

 species. 



The Papilionacere includes about 320 genera 

 and 6,600 species. America leads in the num- 

 ber of peculiar genera, having 82, but Asia 

 leads in the number of species, having about 

 1,700. Africa contains 47 peculiar genera and 

 about 1,600 species, Australia, 38 peculiar 

 genera and about 1,000 species, and Asia 33 

 peculiar genera. Europe, which contains 7 

 peculiar genera and about 700 species, is less 

 rich in both species and genera than any other 

 continent. None of the suljfamilies is con- 

 fined to a single continent but some of the 

 tribes are, the Lipariina; being South African 

 and the Bossiauiue AustraliatL Of the sub- 

 family Podolyriea', 20 out of 27 genera and all 



