14 FOREST TREES OF NORTH AMERICA. 



Rhus is represented by five arborescent species in the Atlantic and by several frutescent species in both the 

 Atlantic and the Pacific regions. 



Pistacia is represented by a single species in the Atlantic-Mexican region. 



Eysenhardtia is represented by a single arborescent species in the Pacific- Mexican, extending into the Atlantic- 

 Mexican region, where a second frutescent species occurs. 



Dalea is represented by a single arborescent species in the Pacific-Mexican and by numerous frutesceut and 

 herbaceous species in the Atlantic and the Pacific regions. 



Robinia, with its center of distribution in the southern Alleghany region, is represented by two arborescent 

 and one frutesceut species in the Atlantic and by one arborescent species in the Pacific region. 



Olneya, an endemic genus of the Pacific-Mexican region, is there represented by a single species. 



Piscidia is represented by a single semi-tropical species. 



Ciadragtis is represented by a single local species in the southern Atlantic region. 



Sophora is represented by a species in the southern Atlantic and by a second species in the Atlantic-Mexican, 

 region, and by four frutescent or sufl'rutescent species. 



Gymnocladus is represented by a single species in the central Atlantic region. 



Gleditschia is represented by two widely-distributed species in the Atlantic region. 



Parkinsonia is represented by an arborescent species common to the Atlantic- and the Pacific-Mexican regions r 

 by two arborescent and one frutescent species in the Pacific-Mexican, and by a frutescent species in the Atlantic- 

 Mexican region. 



Cercis is represented by a widely-distributed species in the Atlantic, by a second species in the Atlantic- 

 Mexican, and a frutescent species of the California Coast region. 



Prosopis is represented by two arborescent species common to the Atlantic- and the Pacific-Mexican regions^ 

 and by two frutescent species. 



Leuccena is represented by two species in the Atlantic-Mexican region. 



Acacia is represented by two arborescent species in the Atlantic-Mexican, by one arborescent species of the 

 Pacific-Mexican extending into the Atlantic-Mexican region, and by several frutescent species widely distributed 

 through the two regions. 



Lysiloma is represented by a single semi-tropical species. 



PithecoloMum is represented by a single polymorphous arborescent species of semi-tropical Florida, and by a 

 shrubby species of the Mexican Boundary region. 



Chrysobalanus is represented by one arborescent and one frutescent semi-tropical species. 



Prunus is represented by seven arborescent species in the Atlantic region ; of these, one is semi-tropical and 

 two extend into the Pacific region. This genus is represented in the Pacific region by four species, ef which one 

 belongs to the Mexican region, and by several frutescent species. 



Vauquelinia, an endemic genus of the Pacific-Mexican region, is there represented by a single species. 



Cercocarpus is represented by two widely-distributed species in the Pacific region. 



Pyrus is represented by one species common to both Atlantic and Pacific, by three arborescent and one 

 frutescent species in the Atlantic, and by one arborescent species in the Pacific region. 



Cratcegus is represented by twelve arborescent and frutescent species in the Atlantic, of which one extends, 

 into the Pacific region, and by two species in the Pacific region. 



Heteromeles is represented by a single species in the Pacific Coast region. 



Amelanchier is represented by one arborescent species in the Atlantic and by one frutesc-int species in the 

 Pacific region. 



Hamamelis and Liquidambar are each represented by one widely-distributed species in the Atlantic region. 



Rhizophora is represented by a single species in the southern Atlantic region. 



Conocarpus, Laguncularia, and Calyptranthes are each represented by a single semi-tropical species. 



Eugenia is represented by five semi-tropical species. 



Cereus is represented by a single arborescent species in the Pacific and by several frutesceut species in the 

 Atlantic and Pacific regions. 



C&rnus is represented by two arborescent species in the Atlantic, by a single arborescent species in the Pacific 

 region, and by several frutescent and herbaceous species in the two regions. 



Nyissa is represented by three species in the Atlantic region. 



Sambucus is represented by one arborescent species of wide distribution in the Pacific, by one species in the 

 Pacific-Mexican extending into the Atlantic-Mexican, by a frutescent species in the Atlantic, by a second frutesceut 

 species in the Pacific, and by a frutescent species common to the Atlantic and Pacific regions. 



Viburnum is represented by two arborescent species in the Atlantic and by several frutesceut species in the 

 Atlantic and the Pacific regions. 



Exostemma is represented by a single semi-tropical species. 



Pinckneya, an endemic genus of the southern Atlantic region, is there represented by a single species. 



Oenipa is represented by a single semi-tropical species. 



