I9I4-] SOUTHEASTERN NORTH AMERICA. 175 



liar genera and about 1,000 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 Lipariinae being South African and the Bossiaeinae 

 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, 1 Asiatic, 1 Mediterranean 

 (Eurasia) and 1 common to North America and Asia. 



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

 of Papilionaceas, the genera Cladrastis and Robinia being arbores- 

 cent. 'In 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 Leguminosae 

 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 where they num- 

 ber 136 species. 



The Leguminosae found in the Wilcox deposits number over fifty 

 species, many of which are individually abundant. They represent 

 the families Mimosacese, Caesalpiniaceae and Papilionaceas, the fourth 

 family of the leguminous alliance, the Krameriaceae, 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 Caesalpiniaceae and 20 to the Papilionaceas. 

 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 Mimosaceas but not to the genus Acacia as commonly under- 

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

 tainly identified as Cccsalpinia but referable to the Caesalpiniaceae are 

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

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



