The Hickories 



223 



of some have a sweet, oily kernel, which was of great importance to the North 

 American Indians who used it for food and for oil; they are of increasing im- 

 portance as food at the present time. 



The Hickories have alternate, deciduous, odd-pinnate leaves, the leaflets usually 

 membranous. The flowers are monoecious, the staminate in slender, drooping 

 catkins borne in clusters, usually of 3, near the base of the young shoot of the 

 season after the leaves have unfolded; their perianth is 3-lobed or sometimes 2- 

 lobed, subtended by an almost free bract, which is longer than the lobes of the 

 perianth; stamens 3 to 10 in several series; filaments short; anthers 2-celled and 

 hairy, each notched at the tip, the sacs opening lengthwise, the connective in- 

 conspicuous. The pistillate flowers are in spike-hke clusters of 2 to 6 at the end 

 of the season's twigs, their i-lobed perianth adnate to the ovary. The ovary is 

 inferior, i-celled; stigmas 2, sessile, spreading. The fruit ripens the first season, 

 is globose, ovoid, or cylindric; the husk becomes dry, hard, and woody, 4-valved, 

 splitting, in most species, to at least the middle, its angles sometimes winged ; nut 

 thick-walled, smooth, mostly compressed, usually 2-celled above, and 4-celled be- 

 low the middle; seed sweet or bitter, without endosperm, 2-lobed, the lobes vari- 

 ously grooved, its coat thin and papery, of two layers, the outer browTi. 



The generic name is adapted from the North American Indian name, and is 

 ten years older than Carya Nuttall. Juglans alba Linnaeus is the type species. 



Cotyledons of the seed entire, or merely notched at the apex; nuts 

 round or slightly flattened; bud-scales valvate. 

 Leaflets 5-9; shell of the nut very thick. i. 



Leaflets 9-15; nuts with very thin shells. 



Nut round; seed sweet. 2. 



Nut somewhat flattened; seed bitter. 3. 



Cotyledons deeply 2-lobed; nuts compressed. 

 Bud-scales valvate; lateral leaflets usually curved. 



Leaflets 9-13, glabrous; nuts corrugated. 4. 



Leaflets 5-9, pubescent beneath; nuts smooth. 5. 



Bud-scales imbricated; lateral leaflets not curved. 



Bract much longer than the lateral lobes of the staminate calyx; 

 husk of the fruit freely splitting to the base. 

 Bark close, rough; foliage scurfy or pubescent. 



Rachis of the leaves and the staminate aments scurfy, at 



least when young. 6. 



Rachis and staminate aments densely hirsute. 7. 



Bark shaggy, separating in plates; foliage glabrous or pubescent. 



Leaflets 7-9; nuts pointed at both ends. 8. 



Leaflets 3-5; nuts usuafly rounded or notched at the base. 



Leaflets oval to oblong-lanceolate, puberulent. 9. 



Leaflets lanceolate, glabrous or glaucous beneath. 10. 



Bract about as long as the lateral lobes of the staminate calyx 

 (except in H. borealis and sometimes in H. glabra); husk 

 of fruit not freely splitting to base. 



H. myristiccBJormis. 



H. Pecan. 

 H. texana. 



H. aqtiatica. 

 H. cordiformis. 



H. pallida. 

 H. alba. 



H. laciniosa.>^ 



H. ovata. 

 H. caroUnx- 



septenlriotialis. 



