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B E T U L A. 



The B I R C H-T R E E. 

 Clafs 21. Order 4. Monoecia Tetrandria. 



*nrHE Male flowers are difpofed in a cylindrical Katkin. 



The Calyx, is a common Katkin, imbricated on all fides, 

 loofe and cylindrical compofed of triflorous ScaleSy to 

 each of which, two very minute fcales are placed at the 

 fides. 



Xhe Compound Corolla confifts of three florets, equal, and affix^ 

 ed to the difk of each fcale of the Katkin. 

 The Proper is monopetalous, four-parted, fpreading, and 

 fmall: the divifions obtufe and egg-lliaped. 



The Filaments are four, very fmall. The Jntherce are twin. 



* The Female flowers are difpofed inKatkins on the fame plant. 



The Calyx is a common Katkin, imbricated; with three fcales 

 every where oppofed, aflSxed to the rachis, heart lliaped with 

 a point, biflorous, a little divided by a pointed body in the 

 bofom towards the top, concave, and fliort. 



The Corolla none manifeft. 



The Germen proper, is ovate, very fmall. The Styles are two, 

 brifl:ly, and the length of the fcales. The Stigmas fimple. 



The Seed-veJJel none. The' Katkin embracing the feeds of twt 

 florets under each fcale. 



The Seeds are folitary and ovate. 



The Species zuith us are^ 



I. Betula nigra. Blacky or Sweet-^Birch. 



This becomes a large tree, often rifing to the height 

 of fifty or fixty feet, and fending off many branches. 

 The leaves are egg-fhaped and doubly or irregularly 

 ferrated, the fmall ferratures are clofe, the larger 

 more remote; their footftalks are villofe. The fmall 

 branches are alfo covered with down. The natives 

 often make their canoes of the bark of this tree. 



2. Betula 



