190 BERRY— LOWER EOCENE FLORA OF [April 25, 



somewhat doubtful form from the Upper Oligocene of France. 

 Similarly the genus Byrsonima L. C. Rich., with 90 existing species 

 ranging from the Bahamas and Mexico to southern Brazil and 

 Bolivia has been recorded by Massalongo from the early Pliocene of 

 Italy, but the identification is extremely doubtful. 



The genus Banisteria Linne contains about 70 existing species 

 of climbing or scrambling shrubs ranging from the West Indies 

 throughout tropical South America. It is represented by four spe- 

 cies based upon both leaves and fruits in the Wilcox ; there is a 

 Ypresian species in the south of England ; four Oligocene species 

 in France, the Tyrol, Alsace and Styria ; and four Miocene species 

 in France, Switzerland and Croatia. 



The genus Banisteriophyllum Ettingshausen with a single Upper 

 Cretaceous and an Eocene species in eastern Australia I regard as of 

 very doubtful affinities. Schenk also states that wood of a malpighi- 

 aceous type occurs among the silicified woods from the Oligocene 

 of the Island of Antigua. 



The family Euphorbiacese is sometimes made the type of a dis- 

 tinct order, the Euphorbiales, although the significance of the char- 

 acters by which it is segregated from the Geraniales is not obvious. 

 It is an exceedingly large alliance with about 220 genera and 4,000 

 existing species (Pax, 1890) of herbs, shrubs and trees, widely dis- 

 tributed throughout the tropical and temperate zones. The genus 

 Euphorbia with over 700 species is perhaps the most widely distrib- 

 uted genus in the family. A very large number of the recent species, 

 particularly those of xerophytic character so closely simulating the 

 Cactacese, are of relatively recent evolution. 



In such a multiplicity of existing genera and species any effort to 

 trace the larger features of distribution would occupy more space 

 than it is worth in the present connection. Four arborescent genera 

 with five species reach the United States in the Florida region, and 

 several additional are naturalized in that area. A considerable, but 

 relatively insignificant, number are recorded during the Upper Cre- 

 taceous and Tertiary. The fossil records will, however, have to be 

 greatly increased before they can be said to shed any definite light 

 on the geological history of the family. Enough is now known. 



