30 Bulletin of the University of Texas 



Page 



r. Fruit an ellip- 

 t i c drupe 

 aboutone inch 



long Leitnera ....... 53 



s. Leaves thick, 



fruit an acorn. Quercus 63 



(3) Blade of leaf serrate or notched, 

 (a) Veins of leaves straight not 

 prominently branched. 

 x. Trees with thorns, fruit a 



pome Crataegus 105 



y. Trees without thorns, 

 (x) Leaves oblique at 

 base, fruit a circular 

 samara, leaves harsh 



to the touch Ulmus 94 



(y) Leaves not oblique at 

 base. 



m. Leaves rounded or 

 isomewhat heart- 

 shaped at base 1-2 

 V 2 ' long, thick ; 

 fruit a globular 

 drupe V inch in 



diameter Planera 97 



n. Leaves thin, buds 

 long sharp pointed, 

 bark smooth, fruit 

 a bur with two tri- 

 angular shaped 



nuts Fagus 62 



o. Leaves thin, the 

 bark of the trunk 

 peeling off in thin 



papery leaves Betula 61 



p. Leaves thin, flower 

 in catkins, fruit 



hop-like Ostrya 59 



q. Leaves thin, fruit 

 a catkin with large 

 leaf like bracts, 

 trunk of tree 



grooved Carpinus 60 



r. Leaves thicker 

 than the preceding, 

 fruit an oval shap- 

 ed woody cone Alnus 61 



