546 EUPHORBIACEAE (SPURGE FAMILY) 



acutely angled ; seeds ovate, acute at one end, 1 mm. long. Sandy soil, HI. to 

 Wise., Minn., and Kan. June-Sept. 



w- -M- Appendages of the involucral glands broad and conspicuous, white and 



petaloid. 



3. E. petaloidea Engelm. Half -erect and spreading ; leaves narrowly oblong, 

 retuse or emarginate ; peduncles 2 mm. in length, longer than the petioles ; pod 

 obtusely angled; seeds nearly 2 mm. long. la. arid Mo., westw. and south- 

 westw. June-Sept. 



4. E. zygophylloides Boiss. Habit of the preceding but taller and more 

 slender; leaves linear; peduncles capillary, 5 mm. long ; capsule deeply 3-sul- 

 cate, the lobes carinate ; seeds obscurely 4-angled. (E. Nuttallii Small.) 

 Limestone barrens, Greene Co., Mo. (Blankinship) to Kan., and southwestw. 



I- -- Leaves suborbicular, 1-3 mm. long ; pod 1-1.5 mm. long. 



5. E. sSrpens HBK. Stems filiform, prostrate, and often rooting; leaves 

 round-ovate, obtuse or cordate at base, only 1-3 mm. long ; stipules membrana- 

 ceous, triangular ; peduncles much longer than the petioles, at length in loose 

 foliaceous lateral clusters ; glands of the very small involucre with minute crenu- 

 late appendages; pods acutely angled; seeds obtusely angled, 1 mm. long or 

 less. Rich soil, s. w. Ont., 111., and la. to Kan., and south w. ; rarely adv. eastw. 



* * Seeds minutely roughened or transversely wrinkled; leaves more or less 



serrulate. 



- Glabrous or nearly so. 

 w- Seeds acutely angled ; leaves 4-12 mm. long. 



6. E. serpyllifblia Pers. Glabrous, prostrate-spreading ; leaves obovate-ob- 

 long, narrowed at the very oblique base, sharply serrulate toward the obtuse apex, 

 6-12 mm. long, often with a red spot ; stipules lanceolate, fimbriate ; peduncles 

 as long as or longer than the petioles, at length, in loose foliaceous lateral clus- 

 ters ; glands of the small involucre with narrow somewhat toothed appendages ; 

 pods sharply angled ; seeds acutely quadrangular, slightly cross-wrinkled, often 

 pitted, nearly 1.5 mm. long. Sandy and alluvial soil, n. Mich. (Farwell) to Mo., 

 Tex., and westw. 



7. E. glyptosp6rma Engelm. Glabrous (or very rarely puberulent), erect- 

 spreading; leaves linear-oblong, mostly falcate, very unequal at base, slightly 

 serrulate toward the obtuse apex, 4-10 mm. long ; stipules lanceolate, seta- 

 ceously divided ; peduncles as long as the petioles, in dense foliaceous lateral clus- 

 ters ; glands of the very small involucre with narrow crenulate appendages ; 

 pods sharply angled ; seeds sharply 4-angled and with 5 or 6 sharp transverse 

 wrinkles, 1 mm. long. Oxford Co., Me. (Parlin, Miss Furbish) ; Fisher's I., 

 N. Y. ; Ont. to Wise., Mo., and westw. 



w- -H- Seeds obtusely angled; leaves 1-3 cm. long. 



8. E. PrSslii Guss. Stem often subsimple below, erect or obliquely ascend- 

 ing, 2-10 dm. high ; leaves oblique at the obtuse or slightly cordate base, ovate- 

 oblong or oblong-linear, sometimes falcate, serrate, 1-3 cm. long, usually with a 

 red spot or red margins ; stipules triangular ; peduncles longer than the petioles, 

 collected in loose leafy terminal cymes ; appendages entire, larger and white, or 

 smaller and sometimes red ; pod glabrous ; seeds ovate, obtusely angled, wrinkled 

 and tubercled, I mm. long, blackish. (E. hypericifolia Man. ed. 5, not L.? E. 

 nutans Lag.) Dry open soil/Mass, to Ont., Wise., Neb., and southw. 



i- *- Puberulent to hirsute. 



9. E. hirsuta (Torr.) Wiegand. Of lower stature and more procumbent than 

 the preceding ; stems hirsute, copiously branched from near the base ; leaves 

 smaller, 8-14 mm. long, oblong to ovate ; seeds black with pale semi-transparent 

 envelope, sharply 4-angled, the flattish or concave sides obscurely wrinkled. 

 (E. hypericifolia, var. Torr.) Dry sandy soil, e. Que. to w. Ont., s. to N. J., 

 Pa., O., and 111., common. 



