82 



LOWER EOCENE FLORAS OF SOUTHEASTERN NORTH AMERICA. 



Artoi-arpus are iudigoiious to the southeasteru 

 Asiatic region, although some of tliem are culti- 

 vated in all tropical countries. Tlie l)r('ailfruit 

 is found throughout Oceanica and was present 

 in Hawaii and the Marquesas, when the}' were 

 first visited hy Europeans. It was introduced 

 into the West Indies in 1793. Of the tribe 

 Euartocarpea?, of which .Vi'tocarpus is the 

 largest existing genus, 5 genera are confined 

 to Central and South .\merica, 1 genus is con- 

 fined to tropical West Africa, 2 to the south- 

 eastern Asiatic region, 1 to Borneo, and 1 

 ranges from Japan to Australia. Though the 

 geologic history of ^Vi-tocarpus is only imper- 

 fectly known, at least 15 different fossil species 

 have been described. The oldest is a well- 

 marked forn^ based on characteristic leaves 

 and parts of the fruit wliich sliow the typical 

 sm-face features. It has been fully described 

 by Nathorst' and comes from the Atane beds 

 (Cenomanian) of west Greenland. Shghtly 

 younger is a less well defined form recorded 

 from the EmscheriaTi of Westphalia and the 

 somewhat doubtful genus Ai-tocarpophyllum 

 of Dawson from the Upper Cretaceous of Van- 

 couver Island. Another species is recorded 

 from the Laramie formation and the genus 

 is widely distributed in the basal Eocene 

 of North .Vmerica. It continues in the GuK 

 region until the close of the Oligocene, the 

 latest recorded occurrence being in the sands 

 of the Alum Bluft" formation at ^Uuni Bluff on 

 Apalaclficola River. On the Pacific coast it is 

 found in deposits in California and Oregon 

 which are referred to the Miocene. In the 

 European area it occurs in the Tongrian of 

 France, the Tortonian of Baden, the Pontian 

 of France and Italy, and the Pliocene of Italy. 

 It is present in both the Pliocene ami Pleis- 

 tocene of the island of Java. 



Artocarpus is said to be represented bj^ pet- 

 rified wood in the Oligocene of the island of 

 Antigua, and it was evidently a member of the 

 American flora from the Upper Cretaceous 

 until late in the Tertiary, althougli. like the 

 genera Cimiamomum, Nipa, Phoniix, and the 

 like, it is not represented in post-Pleistocene 

 American floras. An extmct genus related to 

 Artocarpus and named Artocarpoides by Sa- 

 porta, who described several species from the 



iNathorst, A. G., KongL Svenska Vet.-Akad. Handl., Bd. 24, No. 1, 

 10 pp., 1 pL, 1890. 



Paleocene of France, is represented ])y a single 

 Wilcox species. 



The genus Cecropia, which includes about 40 

 existing species confined to the Tropics of 

 South Ami'rica, has 2 species in the Aquita- 

 nian of Bohemia, and the Midway (?) and Wil- 

 cox form tlescriljetl as Ficus sp. is very prob- 

 ably a representative of this genus. 



The genus Pseudolmedia, wliich has 5 ex- 

 isting species in the American Tropics, has a 

 well-marked species m the Wilcox flora. As 

 far as I know, it has not heretofore been re- 

 corded in the fossil state, although it is prol)- 

 able that some of the numerous fossil species 

 of Ficus may represent Pseudolmedia. 



The genus Ficus is represented by many spe- 

 cies in the Wilcox flora, no less than 18 hav- 

 ing been described, and a number of these are 

 individually abundant. They mclude the nar- 

 row lanceolate forms of the Ficus: thistiai, type 

 with close-set laterals, as well as open-veined 

 lanceolate forms and the shorter and broader 

 palmately veined forms. None are lobate or 

 have toothed margins. Ficus was evitlently 

 much more abundant and varied along the 

 Wilcox coast than it is to-day througliout the 

 West Indies and was more nearly comparable 

 in this respect with the numerous forms of figs 

 in the East Indies or in tropical South America. 



The numV)er of fossil forms that have been 

 referred to Ficus are very numerous, including 

 perhaps 300 species. None are certainly known 

 from the Lower Cretaceous, the genus Fico- 

 phyllum - being entirely doubtful. In the 

 Upper Cretaceous, however, Ficus is very wide- 

 spread and abundant, being represented by 

 characteristic fruits as well as leaves, which 

 seemmgly indicates a Lower Cretaceous ances- 

 try as yet unknown. The Cenomanian has 

 furnished 3 species in Greenland, 6 along the 

 Atlantic coast, and 24 in the interior of North 

 America, as well as 11 in Saxony, Bohemia, 

 and Moravia. The succeeding Turonian fur- 

 nishes 4 species in Bohemia and the Tyrol and 

 several in North America (Tuscaloosa, Mago- 

 thy. Black Creek, and Eutaw formations). 

 Later Upper Cretaceous horizons have numer- 

 ous species of Ficus throughout North America 

 and Europe, as well as in Greenland, Austra- 

 lia, and New Zealand. This cosmopolitanism 



2 Berry, E. W., Maryland Geol. Survey, Lower Cretaceous, pp. 502- 

 506, 1911. 



