352 ASCLEPiADACE^. (milkweed family.) 



2. A. Sullivdntii, Engelm. Mss. Very smooth throughout, tall; leaves 

 ovate-oblong fiom a heart-shaped sessile base, erect; hoods of the crown obovate, entire, 

 obtusely 2-eared at the base on the outside, with a slender but obtuse claw-like 

 horn ; pods ovate-larweolate, vnth smaU and scattered warty spires chiefiy on the beak. 

 — Near Columbus, Oliio, Sullivant. W. Illinois, Engdmann. July. — Resem- 

 bles No. 1 in appearance, in the petals, &c. ; the hoods larger, and exceeding 

 the anthers by one half. 



# # Pods not warty-roughened or prickly, 



*- Leaves all or chiefly opposite, or the middle ones sometimes in fours. 



++ Stems simple or nearly so {above ■usually with 2 lines of minute pubescence). 



3. A. phytolaccoides, Pursh. (Poke-Milkweed.) Stem (3° -5° 

 high) smooth ; leaves broadly ovate, or the upper oval-lanceolate and pointed at both 

 ends, sJwrt-petioled, smooth or slightly downy underneath (5' -8' long) ; pedicels 

 loose and nodding, numerous, long and slender (l'-3' long), equalling the pedun- 

 cle, many times longer than the ovate-oblong divisions of the (greejiish) corolla ; hoods 

 of the crown (white) truncate, the margins 2-toothed at the summit, the horn 

 with a long projecting awl-shaped point ; pods minutely downy. — Moist copses ; 

 common. June. 



4. A. purpurfiscens, L. (Pdeple Milkweed.) Stem rather slen- 

 der (2° -3° high) ; leaves elliptical or ovate-oblong, the lower mucronate, the upper 

 taper-pointed, minutely vdvety-downy undei-neath, smooth above, contracted at the 

 base into a short petiole ; pedicels shorter than the mostly terminal peduncle, about 

 twice the length of the dark purple lanceolate-ovcUe diinsions of the corolla ; hoods of 

 the crown oblong, abruptly narrowed above ; the horn broadly scythe-shaped, with 

 a narrow and abruptly inflexed horizontal point; pods smooth. (A. amcena, L., 

 Michx.) — Border of woods, &c., N. England to Michigan and Kentucky : com- 

 mon westward. July. — Plowers as large as in No. I: peduncle and pedicels 

 downy along one side. 



5. A. variegata, L. (Variegated Milkweed.) Nearly smooth 

 (1° -2° high); leaves ovate, oval, or obovate, somewhat wavy, mucronate, con- 

 iracied into short petioles ; pedicels ( numei'ous and crowded) and peduncle short, downy ; 

 divisions of the corolla ovate (white) ; hoods of the crown orbicular, entire, the 

 horn semilunar with a horizontal point ; pods sUghtly downy. (A. nivea, L., 

 in part. A. hybrida, Michx.) — Dry woods, S. New York to Wisconsin and 

 southward. July. — Remarkable for its very compact umbels of nearly white 

 flowers, often purple in the centre. Leaves 4-5 pairs, the middle ones some- 

 times whorled ; veins often purple. Peduncles 1-3, usually ^' long. 



6. A. Nuttalliana, Ton-, (excl. char.?) Low (6' -15' high), soft- 

 downy, especially the lower side of the ovate or lance-oblong acute slightly petioled 

 leaves; umbels loosdy 10 - IS-fhuKred, either sessile or peduucled ; pedicels slen- 

 der (J'- 1' long) ; hoods of the crown oblong, obtuse, yellowish, with a small 

 horn, about the length of the oval greenish-white divisions of the corolla (which 

 are tinged with purple outside). (A. lanuginosa, iVuff.) — Prairies and Oak- 

 openings, N. Illinois, Vasey, Wisconsin, Lapham, and westward. June. — 

 Leaves l|-'-3' long, i'-lj' wide, smoothish above, the upper sometimes scat- 

 tered. Flowers about as large as in the next. 



