24(5 BERRY— LOWER EOCENE FLORA OF [April 25, 



corded an Upper Cretaceous species, Nerium Rohlii, from the Cam- 

 panian of Westphalia but this is almost certainly a member of the 

 Myrtaceae and not a Nerium. Undoubted species do occur in the 

 Eocene of Europe, including the remains of a characteristic flower 

 from the Paris basin. There are several Oligocene and Miocene spe- 

 cies in Europe and the existing Nerium oleander or its immediate 

 ancestor occurs in the Pliocene of southern Europe in France and 

 Spain. The Wilcox species Apocynophyllum tdbellarum is very sug- 

 gestive of Nerium but the genus is not certainly known in the 

 western hemisphere. 



It may be noted that with the exception of the not certainly 

 identified species of Apocynophyllum the family is not represented in 

 the abundant known Upper Cretaceous floras of the world, which 

 might mean that it originated somewhere in the southern hemisphere. 



The order Polemoniales or Tubiflorre 49 contains the four families 

 Convolvulaceae, Polemoniaceae, Hydrophvllaceae and Borraginaceae. 

 The first three are characteristically American, the Convolvulaceae 

 being chiefly tropical, while the largest family, the Borraginaceae, is 

 typically developed in the north temperate zone. 



The family Borraginaceae, the only one of the order known in the 

 Wilcox flora, contains about 85 genera and 1,600 existing species of 

 mostly widely distributed north temperate herbs and shrubs, or 

 trees in tropical countries, characterized by alternate, exstipulate, 

 mostly entire leaves. The known fossil forms are few in number 

 and of slight significance and comprise for the most part Tertiary 

 remains described as species of Borraginites and Heliotropitcs. The 

 family is represented in the Wilcox by two species of Cordia, a genus 

 containing about 230 existing species of shrubs and trees of the war- 

 mer regions of both hemispheres, especially the western. There is a 

 species in the Upper Cretaceous of the Misssissippi embayment area 

 (Tuscaloosa formation) and a Miocene species in Europe. Early 

 Tertiary forms are recorded from Chili by Engelhardt and from 

 Tasmania by Ettingshausen. The slight evidence available indicates 

 that the genus originated in the American tropics and that the bulk 

 of the family is of late Tertiary origin. 



* 9 Not tin- Xubiflorac of Engler which includes the orders Polemoniales 

 and Personales, here regarded as distinct. 



