Thèse prints are a reproduction of the set of tracings now in 

 the National Herbarium made frora the copy of Moscino h Sesse tra- 

 cings given to Dr.Asa Gray by M . A . De Can do 1 le . The ac company ing 

 index and préface are a part of the original édition ard have been 

 procured through the kindness of Casimir DeCandolle. 



