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. 
Juctans, 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 
