132 TREES OF NORTH AMERICA 



in the axils of lanceolate acute persistent bracts; calyx usually 2 rarely 3-lobed, 

 its bract free nearly to the base and usually much longer than the ovate rounded 

 calyx-lobes; stamens 3-10, in 2 or 3 series, their anthers ovate-oblong, emarginate 

 or divided at the a])ex, pilose or hirsute, as long or longer than their slender con- 

 nectives; pistillate flowers sessile, in 2-10-flowered spikes, with j)erianth-like involu- 

 cres, slightly -l-ridged, une(pially 4-lobed at the apex, villous on the outer surface, 

 the bract much longer than the bractlets and single calyx-lobe ; stigmas short, 

 papillose-stigmatic. Fruit ovoid, globose or pyriform, with a lliiii oi- thick husk 

 becoming hard and woody at maturity, 4-valved, the sutures alternate with those of 

 the nut, sometimes more or less broadly winged, splitting to the base or to the mid- 

 dle; nut oblong, obovate or subglobose, acute, acuminate, or rounded at the apex, 

 tipped by the hardened renmants of the style, narrowed and usually rounded at the 

 base, cylindrical or compressed contrary to the valves, the wall thin and brittle or 

 thick, hard, and bony, smooth or variously rugose or ridged on the outer surface, 

 -l-celled at the base, 2-celled at the apex. Seed compressed, variously grooved on 

 the back of the flat or concave lobes, sweet or bitter. 



Hicoria is confined to the temperate region of eastern North America from the 

 valley of the St. Lawrence River to the highlands of Mexico. Of the twelve species, 

 eleven inhabit the territory of the United States. 



The generic name is formed from the popular name of these trees. 



CONSPECTUS OF THE NORTH AMERICAN SPECIES. 



Bud-scales few, valvate, the inner strap-shaped and only slightly accrescent ; fruit more or 

 less broadly winged at the sutures ; shell of the nut thin and brittle, with large cavities 

 {thick in 4)' 



Aments of staminate flowers nearly sessile, usually on branches of the previous year. 

 Leaflets 13-15, oblong-lanceolate, more or less falcate ; nut ovate-oblong, cylin- 

 drical ; kernel sweet. 1. H. Pecan (A, C). 

 Leaflets 7-11, lanceolate, often falcate ; nut oblong, compressed ; kernel bitter. 



2. H. Texana (C). 

 Aments of staminate flowers long-stalked on branches of the year or of the previous 

 year. 



Leaflets 7-11, lanceolate or oblong-lanceolate ; nut often broader than long, slightly 

 4-angled ; kernel bitter. 3. H. minima (A, C). 



Leaflets 7-11, ovate-lanceolate to lanceolate-obovate ; nut ellipsoidal, cylindrical, 

 thick-shelled ; kernel sweet. 4. H. myristicaef ormis (C). 



Leaflets 7-13, lanceolate, more or less falcate ; nut compressed, rugose, prominently 

 ridged ; kernel bitter. 5. H. aquatica (C). 



Bud-scales numerous, imbricated, the inner becoming much enlarged, often highly colored 

 and much reflexed and twisted before falling ; aments of staminate flowers at the base 

 of branches of the year, long-stalked ; fruit without sutural wings {sometimes slightly 

 winged in 11) ; shell of the nut thick and bony, wnth minute cavities. 

 Bark separable from old trunks in long loose plates. 

 Branehlets light red-brown ; nut pale or nearly white. 



Leaflets 5-7, ovate to oblong-lanceolate or obovate ; nut thick or thin-shelled ; 

 branehlets stout. 6. H. ovata (A, C). 



Leaflets usually 5, lanceolate ; nut thin-shelled ; branehlets slender. 



7. H. Carolinae-septentrionalis (C). 

 Branehlets pale orange color. 



Leaflets 5-9, obovate or oblong-lanceolate, puberulous on the lower surface ; nut 

 ovate, thick-walled, prominently 4-angled, dull white to light reddish brown. 



8. H. laciniosa (A, C). 



