STUDIES OF TREES IN WINTER 



2. LEAF-SCARS ALTERNATE (continued). 



Branchlets stout except in Magnolia mrginiana ; 



buds acute. Magnolia. (Magnolia, p. 153.) 



b. Branch without a terminal bud, prolonged by the 



growth of an upper axillary bud. 

 Bud scales numerous (except in Ailanthus.} 

 Twigs slender. 



Twigs with conspicuous catkin-buds. 



Buds slender, elongated, sticky. Birch. (Be- 



tula, p. 59.) 

 Buds ovate, elongated. Hop Hornbeam. 



(Os(rya,p. 71.) 

 Buds small, obtuse. "Hornbeam. (Carpinus, 



p. 72.) 

 Twigs without catkin-buds. 



Buds ovate, acute, dark brown ; pith not cham- 

 bered. Elm. (Ulmus, p. 101.) 

 Buds ovate, acute ; pith white, chambered. 



Hackberry. (Celtis, p. 112.) 

 Buds obtuse, chestnut brown, superposed ; flower- 

 buds oval. Judas Tree. (Cerds, p. 136.) 

 Twigs stout. 



Buds flattened, covered by two outer scales ; pith 

 chocolate brown. Ailanthus. (Ailanthus, 

 p. 160.) 

 Bud scales only one; buds ovate. Buttonwood. 



(Platanus, p. 117.) 

 Buds naked (without scales). 



Buds axillary, superposed, four together, flat- 

 tened by mutual pressure into an acuminate 

 cone; branchlets slender. Yellowwood. 

 (CladrasttS) p. 134.) 



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