SPURGE FAMILY. 381 



oblong-linear, obtuse and mucronate ; lobes of the involucre longer than 

 the minute and unappendaged glands. 



= = Seeds minutely roughened or wrinkled; leaves serrulate, and the 

 plant often hairy. 



E. glyptosp^rma, Engelm. Glabrous or rarely slightly puberulent, 

 erect or spreading ; leaves linear-oblong and mostly falcate, very unequal 

 at the base, serrulate near the obtuse apex ; stipules lanceolate and cut ; 

 seeds sharply 4-angled, marked with 5 or 6 sharp transverse wrinkles. 

 Ontario, W. 



E. maculata, Linn. Prostrate ; leaves oblong-linear, very oblique at 

 base, serrulate above, blotched in the center ; pods sharp-angled, very 

 small, with 4 shallow grooves. Common along roads and in dry fields. 



E. humistrata, Engelm. Procumbent, hairy, or puberulent ; leaves 

 elliptic or obovate, very oblique at the base, sparsely hairy underneath, 

 sometimes with a brown spot on the upper side ; involucre cleft on the 

 back, the truncate or crenate appendages red or white ; seeds ovate, 

 obtusely angled and minutely roughened. Rich places, Ind., W. 



E. Pr^slii, Guss. Ascending 10'-20' high; leaves ovate-oblong or 

 linear-oblong, serrate, often with red spot or margins; appendages 

 entire ; pod blunt-angled ; seeds ovate, obtusely angled, wrinkled and 

 tubercled, blackish. Common. 



** Leaves opposite or whorled at the top of the stem, alternate or scat- 

 tered below, larger; plants strict. 



E. marginata. Pursh. SNOW ON THE MOCNTAIN. Wild on the plains 

 W. of the Mississippi, and cult, for ornament ; leaves pale, ovate or oval, 

 sessile, the lower alternate, uppermost in threes or pairs and broadly 

 white-margined ; flower-cup with 5 white petal-like appendages behind 

 as many saucer-shaped glands. Stout, 2-3 high. 



E. cprollata, Linn. Gravelly or sandy soil, from N. Y., S. and W.; 

 2-3 high ; leaves varying from ovate to linear, entire, the lower alter- 

 nate, upper whorled and opposite ; flower cups umbelled, long-stalked, 

 with 5 bright white conspicuous appendages, imitating a 5-cleft corolla. 2i 



- *- Glands of the involucre destitute of petal-like appendages. 



** Involucres (or "./forcers") in terminal clusters, with few or solitary 

 glands ; all, or the uppermost, leaves opposite, variable ; stipules small 

 and glandular. 



E. dentata, Michx. Rich soil from Penn. S. and W.; hairy, only the 

 lower leaves alternate, the upper opposite, varying from ovate to linear, 

 uppermost paler or whitish at base, and the few glands of the flower cup 

 short-stalked. 



E. heterophylla. Linn. Glabrous ; leaves alternate, ovate and sinuate- 

 toothed, or fiddle-shaped, or some of them lanceolate or linear and 

 entire ; the upper with red base ; no petal-like appendages to the flower 

 cup and only 1 or 2 sessile glands. Minn., S. 



* -M- Involucres in a terminal forked or umbel-like inflorescence, icith 4 or 

 5 entire or crescent-shaped glands; plants ascending or erect, generally 

 glabrous; stipules 0. 



= Leaves of the commonly erect stem alternate or scattered ; those of the 

 umbel-like inflorescence whorled or opposite and of different shape, 

 usually roundish; glands of the flower cup mostly 4. Weeds or weed- 

 like. 



B Glands of the flower cup or involucre transversely oval and obtuse. 



. platyphylla, Linn. Xat. from Eu. N.; upper stem-leaves lance-oblong- 

 acute, minutely serrulate ; uppermost heart-shaped ; floral ones triangu- 



