I9M-] SOUTHEASTERN NORTH AMERICA. 227 



tania-Yike fruits have been described as Tristanitcs by Saporta from 

 the lower Miocene of France: the genus Psidium Linne, with about 

 ioo modern species in the West Indies and Mexico, is represented in 

 Chili by an early Tertiary species : and finally the genus Metrosi- 

 deros has been identified in the Atane beds of Greenland and in both 

 the Oligocene and Miocene of Europe. 



The family Combretaceae (Terminaliaceas) embraces about 16 

 genera and 285 existing species of shrubs or trees and tropical 

 vines, with simple, entire, coriaceous, persistent, exstipulate, alternate 

 or opposite leaves. The inflorescence is racemose or capitate and 

 the flowers are regular, perfect or polygamous, often apetalous. The 

 stamens are two or three times as numerous as the petals and the 

 one-celled ovary develops into a drupaceous or berry-like indehiscent 

 fruit, often crowned with the accrescent calyx and containing a soli- 

 tary seed without endosperm. 



The existing species are all tropical or subtropical, ranging from 

 34 north to 35 ° south latitude, and a relative large number are lit- 

 toral or strand types. The various continental areas have the fol- 

 lowing peculiar species: America 75, Africa 85, Madagascar 36, 

 Asia 57, Australia 23. About ten or a dozen species are found in 

 more than one area, there being a remarkable identity between the 

 American tropics and those of West Africa, the genera Cacoucia, 

 Conocarpus and Laguncularia having identical species in both 

 regions. 



The geologic history of the family is most incomplete, but it is 

 exceedingly prominent in the Wilcox flora where it is represented 

 not only by characteristic leaves but by flowers and fruits. No spe- 

 cies are certainly known from horizons as old as the Upper Creta- 

 ceous although a species of Termanaliphyllum has been described 

 from the Perucer beds (Cenomanian ) of Bohemia and a species of 

 Conocarpites from the Tuscaloosa formation of Alabama. So far 

 as I know there are no authentic occurrences as old as those of the 

 Wilcox. In this flora there are three well-marked species of Com- 

 bretum, a genus with about 130 existing species found in all tropics 

 except Australia and Polynesia. Over thirty of these are endemic 

 in South America and their abundance in the Wilcox as well as the 



