JUGLANDACEAE. 59 



tinuous white pith; alternate little raised half-elliptical or tri- 

 angular leaf-scars with 3 bundle-traces ; no stipule-scars ; ovoid 

 sessile buds with several exposed scales ; moderate entire petioled 

 leaves ; dioecious apetalous flowers in catkins ; and dry drupe- 

 like wrinkled fruit. 

 Leaves lance-elliptical, hairy beneath. L. floridana. 



Family JUGLANDACEAE. Walnut Family. 

 A small widespread family furnishing most of the nuts of 

 commerce and the important hard woods hickory and walnut; 

 sometimes planted for shade trees. 



JUGLANS. Walnut, Butternut. 



Deciduous mostly large trees with brown wood with mod- 

 erate fairly uniform diffused ducts and fine medullary rays with 

 tangential bands of wood parenchyma; stout roundish twigs; 

 rather heart-shaped triangular or 3-lobed large leaf-scars with 3 

 crescent-shaped or compound bundle-traces ; no stipule-scars ; 

 superposed buds with several, sometimes lobed, scales ; large odd- 

 pinnate leaves ; small monoecious apetalous flowers in catkins ; 

 and large nuts with hard shell enclosed by an indehiscent fleshy 

 pericarp. 



1. Leaf-scars with a downy cross-line at top. 2. 

 Leaf-scars without a downy ridge at top, notched. 3. 



2. Twigs moderate : leaf-scars not notched. J. cinerea. 

 Twigs stout: leaf-scars notched. (Japanese). J. Sieboldiana. 



3. End buds elongated : nuts small. J. rupestris. 

 End buds scarcely longer than thick : nuts large. 



4. Buds ashen-pubescent. (Black walnut). J nigra. 

 Buds glabrate. (European walnut). J. regia. 



PTEROCARYA. 



Deciduous trees with pale wood with rather sparse and small 

 diffused ducts and fine medullary rays with wood-parenchyma 

 cross-lines ; moderately stout terete twigs ; somewhat 5-sided 

 brownish chambered pith; alternate 'somewhat raised obtusely tri- 

 angular or 3-lobed leaf-scars with 3 compound bundle-traces ; 

 no stipule-scars ; scaly and solitary, or naked and superposed 



