so 



LOWER EOCENE FLORAS OK SOUTHEASTERN NORTH AMERICA. 



Oriouti and Oreomiuuioa in tlio Occidout in 

 outliiie. Those areas are somewhat general- 

 ized and exaggerated iu order to be sho\\ai on 

 a map so small in scalii. The areas where 

 Tertiary species of l*]ng('.Diardtia have been 

 foimil are mdicated liy circles, iuid tiiough the 

 map is not as complete as might be desired, it 

 shows very clearly that foiTus closely allied to 

 the modem Eugelliardtia were widespread 

 during the Tertiary period, when the more 

 extensive wann climate enabled them to ]5ene- 

 trat* more th.xn halfway across the North 

 Temperate Zone. It seems probable that they 

 also pushed southward into the South Tem- 



have sho\m in the systematic j^ai-t of this 

 ^\■ork. Probably it I'opresents a suiwival of 

 the ancestral stock from which Engelhardtia 

 was tlerived, smce its fruits are more primitive 

 and hidicatie ancestral fomis with smaller 

 bracts, comparable with the bracts of Juglans 

 or Hicoria, which in the course of time became 

 accrescent and subsequently^ deeply trilobate. 

 Tl\e pi'imitive chai'acter of ParaongeUiardtia 

 and the presence of true EngeUiardtias m the 

 Wilcox so much earlier than their first occur- 

 rence in Europe suggest that .America was the 

 original home of the Engelhardtia stock, al- 

 though this supposition can not be verified or 



cf 





Figure 5. — Sketch map showing areas of distribution of recent and fossil species of Engelhardtia and Oreomunnea. 



perate Zone, but this caix neither be verified 

 nor disproved, for practically no fossil plants 

 of Tertiary age have been discovered ui South 

 America or Africa. It is also probable that 

 carefid ex]>loration will disclose living repre- 

 sentatives of tliis widespread Tertiary stock in 

 western BrazU, es]jecially as they have sm*- 

 vived m Central America north of the Equator. 



Tlie existing EngeUiardtias are upland foi-ms, 

 which may also have been true of the Wilcox 

 species, although their abundance at different 

 localities along the Wilcox coast would seem to 

 mdicate othen\dse. 



The genus Paracngelliardtia, which is a 

 miiquc type confined to a sijigle locality in the 

 Wilcox, is clearly allied to Engelhardtia, as I 



disjjroved until a Tertiary paleobotanic r(«'ord 

 for the continent of Asia is available. 



The MjTicales of the Wilcox flora contain 

 but two species of MjTica. Mp-ica is a very 

 old generic type and has a large number of 

 fossil species, ranguig from the middle Creta- 

 ceous to the present. The existuig species are 

 relatively few m nmnber, arc widely scattered 

 geographically, and represent sm-vivors from a 

 Tertiary cosmopolitan distribution. The allied 

 monotypic genus C()m])tonia, which by some 

 students is hicludcd ui Mp'ica, has an extended 

 geologic histoiy which I discussed' in 1906. 

 Myrica is mucli less abundant in the Wilcox 

 than m the Em'ojxian Tertiary, although it 



• Berry, E. W., Am. Naturalist, vol. 40, pp. 485-520, pis. 1-4, 1906. 



