99 MISSOURI BOTANICAL GARDEN. 
2. Seeds carunculate, calyx obscure, discoid or triangular, invo- 
lucres usually longer than their peduncles. 
* Seeds smooth. (See also E. chamaesula and related species 
when immature). 
+ Rays 3; annual. E. Helleri. 
tt Many rayed; perennial. 
Capsules verrucose, leaves linear; not over a foot high. 
E. Cyparissias. 
Capsules slightly roughened or smvoth, leaves lanceo- 
late; over a foot high. 
Stem leaves less than 1.5 cm. wide. E. Esula, 
Stem leaves over 1.5 cm. wide. E. lucida. 
** Seeds tuberculate; low annual with acute floral leaves. 
E. exigua. 
*** Seeds with rows of pits, at least on the ventral side; annuals, 
usually with obtuse floral leaves. 
+ Capsule crested. E.. Peplus, 
tt Capsule smooth, or nearly so. 
Two sulci on the inner face of the seed. E. peplidion. 
Several pits on the inner face of the seed. 2. tetrapora. 
**** Seeds irregularly covered with pits or ridges. 
+ Thin leaved annuals. 
t Seeds with small deep pits. 
Floral leaves very unequal, longer than the internodes. 
E.. longicruris. 
Floral leaves nearly symmetrical, shorter than the 
internodes. E. commutata. 
tt Seeds with broad pits, and ridges between. 
Floral leaves connate to the middle; in Texas. 
E. Roemeriana. 
Floral leaves connate at the base or to the middle on 
one side; Pacific slope. EF. crenulata. 
tt Perennials. 
¢ Horns of the glands longer than their body. 
Seeds punctate pitted; central United States. 
E. commutata. 
Seeds with broad shallow pits; Pacifics'’ope. Z.crenulata. 
ti Horns of the glands shorter than their body. 
|| Glands crenate and very short horned, lobes oblong. 
4 Stem leaves widest above the middle. 
§ Stem leaves obtuse, floral leaves broader than long. 
Glabrous. E. Palmeri. 
Pubescent. E. subpubens. 
§§ Stem leaves obtuse, floral leaves as long as broad. 
£. lurida. 
§§§ Stem leaves acute. E. lurida Pringlei, 
{J Stem leaves widest at or below the middle. 
E. schizoloba. 
