WINTER KEY TO THE SPECIES OF ULMUS 



a. Buds conspicuously rusty-tomentose; twigs more or less 

 pubescent ; inner bark very mucilaginous when chewed .... 



U. fulva, p. 125. 



aa. Buds not conspicuously rusty-tomentose ; twigs glabrous ; 

 inner bark not mucilaginous, 

 b. Bundle-scars usually 3; buds ^ inch long, glabrous; twigs 



without corky ridges; outline of tree vase-shaped 



U. amencana, p. 127. 



bb. Bundle-scars usually 4-6 in a curved line; buds J4 inch 

 long, somewhat pilose; twigs often with corky ridges; 

 outline of tree narrow-oblong U, racemosa, p. 129. 



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