50 EXPOSITION OF THE LINKEAN 



Jussieu and some other writers), which might contain 

 all genera with separated Flowers, whose accessory 

 organs differ in any respect. This alteration has been 

 adopted by an able practical botanist, whose experience 

 had taught him to approve it, Mr. Frederick Pursh, 

 in his Flora America Septentrionalis, published in 

 1814. He has divided the Class Diclmia into the 

 three following Orders. 



J. SEGREGATE. Flowers not Amentaceous (53:3). 



2. AMENTACE.H. Barren Flowers, at least, in Cat- 

 kins (55 : 3); the Fertile ones not always so. Fruit 

 distinct from the Calyx, fig. 274, 275. 



3. CONIFERJE. Barren and Fertile Flowers in Cat- 

 kins. Fruit a Strobilus or Cone, (61:7) fig. 276. 



Under each Order of the Linnrean System, are dis- 

 posed the Genera which belong to it, in a regular se- 

 ries, as nearly as possible according to their natural 

 affinity to each other, with the Essential Character 

 (104) of each. The Species are, in like manner, ranged, 

 according to their affinities, under each Genus, with 

 their Specific Characters. Synonyms are subjoined, 

 with mention of the native country of each Species ; 

 after which follow occasionally compendious descrip- 

 tions, with any useful remarks. Some large Genera 

 are commodiously divided into Natural Sections, by 

 leading characteristics of certain Species taken col- 

 lectively. 



-At the head of every Class, all its Orders are enu- 

 merated ; and under each Order its appropriate Ge- 



