1914-] SOUTHEASTERN NORTH AMERICA. 175 



liar genera and about i,ooo species. Asia has 33 peculiar genera, 

 while Europe with 7 peculiar genera and about 700 species is less 

 rich in both species and genera than any other continent. None of 

 the subfamilies are confined to a single contintent but some of the 

 tribes are, the Lipariinse being South African and the Bossiseinse 

 being Australian, while 20 of the 27 genera and all but 63 of the 436 

 species of the subfamily Podolyrieae are Australian. Two genera in 

 this subfamily are American, 2 African, i Asiatic, i Mediterranean 

 (Eurasia) and i common to North America and Asia. 



In the eastern United States there are 46 genera and 194 species 

 of Papilionacese, the genera Cladrastis and Robinia being arbores- 

 cent. Un the southern states there are 55 genera and 318 species. 

 Sargent's " Manual of North American Trees," which includes many 

 tropical forms of the Florida Keys, enumerates for the Leguminosas 

 as a whole only 34 arborescent species for North America in 17 

 genera. 



In Grisebach's flora of the British West Indies the Leguminosae 

 outnumber all other families of flowering plants with 262 species. 

 The same is true of Urban's flora of Porto Rico w^here they num- 

 ber 136 species. 



The Leguminosse found in the Wilcox deposits number over fifty 

 species, many of which are individually abundant. They represent 

 the families Mimosacese, C^esalpiniaceas and Papilionacese, the fourth 

 family of the leguminous alliance, the Krameriacese, being a small 

 herbaceous group of the New World of very late, probably of re- 

 cent, evolution. 



Of these fifty-odd Wilcox species eleven are referred to the 

 Mimosacese, 26 to the Csesalpiniacese and 20 to the Papilionace?e. 

 Definitely recognized genera are named in the usual way. Forms 

 usually identified as species of Acacia (as for example most of those 

 so named by Heer, Ettingshausen, Unger, etc.) which are referable 

 to the Mimosacese but not to the genus Acacia as commonly under- 

 stood are referred to the form-genus Mimosites. Forms not cer- 

 tainly identified as Cccsalpinia but referable to the Csesalpiniace^e are 

 classed under the form-genus Cccsalpinitcs while a considerable num- 

 ber of Glcditsia-Wkt forms of both leaves and pods are described in 



