I9I4.] SOUTHEASTERN NORTH AMERICA. 185 



The only genus represented in the Wilcox is Simarnha Aublet, 

 which has furnished a single species, Simaruba cocenica Berry, 

 closely resembling the existing Simarnha glauca De Candolle which 

 is found along tropical coasts from southern Florida to Brazil. 



The only other genus with a geological history is Ailanthus Desf. 

 which has 7 existing species of eastern Asia and the East Indies. ^^ 

 The fossil species number about fifteen. There are two in the 

 Eocene of Wyoming and Oregon ; eight in the Oligocene of France, 

 Alsace, Styria and Prussia ; and five in the Miocene of France, 

 Switzerland, Baden, Italy and Colorado. While in the absence of 

 collateral evidence that the Eocene occurrences in North America 

 have any significance regarding the origin of the genus it is an in- 

 teresting speculation that the genus originated in North America 

 and subsequently reached Asia by way of the Eocene land connec- 

 tion across Behring straits. Certainly the genus lingered on this con- 

 tinent, as is evidenced by its presence at Florissant, as late as the 

 Middle Miocene. 



The family ^Meliacese contains about 42 genera and about 680 

 existing species of shrubs and trees with pinnate leaves. The vast 

 majority are found within 30 degrees of the equator although they 

 reach 40° north in eastern Asia and 40° south in New Zealand. 

 Moreover the China berry (MeMa azcdaracli) has been cultivated 

 from time immemorial in all Mediterranean countries, and through- 

 out the southeastern United States since its settlement, and is per- 

 fectly hardy. There are no temperate outliers however. While the 

 Aleliacese occupy a greater continuous area in South America where 

 over 41 per cent, of the existing species occur, this large number of 

 species (about 285) represent only 19 per cent, of the known genera. 

 There are some remarkable similarities between the species of the 

 American tropics and those of W'est Africa. Thus the two small 

 genera Szvietenia and Carapa are represented in both areas and 

 Carapa procera is even said to be common to the two. Moreover the 

 genus Guarca which has about 80 species in the American tropics has 

 three in West Africa. The larger number of genera are found in 

 the S. E. Asiatic region and the number of genera and their mutual 



^"^ AlianthophyUiim Dawson with a single species is described from the 

 Eocene (?) of British Columbia. 



