BETULACEAE (BIRCH FAMILY) 



47 



C. glabra. Pignut Hickory. The bark does not exfoliate. The 

 seed is bitterish. Nut thick walled. Leaflets 5-7. Winter buds 

 brownish, rounded. 



C. cordiformis, Bitternut Hickory. Like C. glabra, but leaflets 

 7-11, and nut thin-walled. Winter buds yellow, pointed. 



BETUIACEAE (Birch Family) 



Monoecious trees or shrubs. Leaves simple, alternate, and 

 straight veined, and with deciduous stipules. 

 The staminate flowers in catkins, the pistillate 

 ones in clusters, spikes, or in scaly catkins. 



CORYLUS 



Shrubs or small trees, with doubly-toothed 

 leaves. Flowers in early spring. The stam- 

 inate catkins arise from the scaly buds of the 

 axils of the preceding year, while the pistil- 

 late ones terminate the early leafy shoots. 

 The nut is enclosed in a leafy cup formed by 

 the two bractlets enlarged and often grown 

 together and lacerated at the border; cotyle- 

 dons very thick ; sweet and edible. 



Corylus americana. 

 Hazelnut. 



C. americana, Hazelnut. 

 lucre open above. Thickets. 



Leaves roundish-heart-shaped. Invo- 



OSTRYA 



Slender trees with very hard wood, brown- 

 ish furrowed bark, and leaves resembling 

 those of birch. The flowers appear with the 

 leaves. The fruit is enclosed in a bladdery 

 bag (the inflated involucre), which is much 

 larger than the small smooth nut within. .This 

 ^ , ... „„„ inflated involucre gives an appearance like 



Ostrya virgtniana, Hop o ^r ^ 



hornbeam. Pistillate that of the fruit of hops. 

 and staminate cat- 

 kins. O. virginiana. Hop Hornbeam. Leaves oblong- 



