36 MISSOURI BOTANICAL GARDEN. 
Nebraska, south to Texas and Florida,— in various situa- 
tions.— Pl. 5, 6, 13, f. 10-12, 16, f. 4-6. 
Apparently the Bitternut hybridizes with the Pecan, . 
the hybrids more or less closely approaching the former in 
twig and foliage characters and in the thinness of shell and 
the form of the nut, while they more nearly resemble the 
latter in the striping and nearly 2-celled structure of the 
nut, which, while less bitter than in true minima, is usually 
decidedly astringent. 
* * Buds always truly scaly, their scales 10 or more, imbricated or the 
outermost on lateral buds usually a closed sac soon splitting from 
the top, the inner hairy; staminate catkins at the base of the new 
growth only, each group of three on an exserted common pe- 
duncle; nuts (except in forms referred to under ovata and laciniosa) 
firm shelled, 4-celled at base; kernel not ruminated.— § Euhicoria 
or Fucarya. 
+ Buds small (5 to 10 mm. long), becoming subglobose toward 
spring, their outer scales commonly glandular dotted; twigs 
glabrate, cherry colored to gray, slender for the group. 
5. H. auasra (Miller) Britton. Carya porcina, Nut- 
tall._— The Pignut.— A medium sized tree; bark thick, 
dark gray, checked much like that of the mature white 
ash; twigs purplish to dull gray, often without conspic- 
uous lenticels; buds reddish brown to gray, silky after 
parting the outer scale; fruit about an inch long, pyriform, 
mostly apophysate, elliptical in cross section; husk about 
1 mm. thick, rarely splitting far, and never below the 
middle; nut ellipsoidal, not angled, pointed from the mostly 
sunken apex, usually mucronate at the base, dirty brown; 
shell about 2 mm. thick, the commissure stout; kernel of 
inferior quality. Two forms of fruit occur, the longer 
marking the variety ficiformis, and the shorter the variety 
obcordata, but these appear scarcely worthy of varietal 
separation.— So far as my specimens show, limited to the 
Atlantic region, from Massachusetts and Pennsylvania to 
Florida.— Pl.’7, 14, f. 1, 17, f. 5-6. 
Var. oporATA (Marshall) Sargent.— Bark rough fis- 
sured, as in the Mockernut, or sometimes resembling the 
