POLYGONACEAB (BUCKWHEAT FAMILY) 



359 



710. P. aviculare. 



a. Typical form x %, 



b. V. littorale x %. 



0. Stem-leaf of v. veg^etum x %. 

 d. Stem-leaf of V. angust. x%, 



doubtless elsewhere. 

 6. P. er^ctum L. 



Var. littor^ie (Link) Koch. Leaves 

 thick, often obtuse ; achenes slightly 

 shining, obscurely punctate or punctate- 

 striate. (P. littorale Link. ) — A mari- 

 time and littoral form sometimes char- 

 acteristic, but passing to tlie typical 

 form and separated by. no constant 

 character. (Eu.) Fig. 710 6. 



Var. vfigetum Ledeb. Larger, erect 

 or nearly so ; the leaves (often 3 cm. 

 long) oblong or narrowly elliptic, thin, 

 the margins crisped. — Rich soil dnd in 

 shade. (Eu.) Fig. 710 c. 



Var. angustissi- 

 mum Meisn. 

 Leaves linear, 5-9 

 times as long as 

 broad. — Summit 

 of Mt. Monad- 

 nock, N. H., and 

 (Eu.) Fig. 710 d. 

 Stout, erect or ascendingj yellovrish- 

 gi-een; leaves elliptical, 1.3-6 cm. 

 long, usually obtuse ; flowers yel- 

 lowish-green, about 3 mm. long, 

 on more or less exserted pedicels; 

 stamens 5-6; achene dull, included. 

 — Waysides, waste places, etc. Fig. 

 711. 



7. P. ramoslssimum Michx. 

 Erect or ascending, 0.6-1 .9 m. high, 

 yellowish-green ; leaves lanceolate (2-5 cm. long), 

 acute ; sepals 6, the 3 outer 2-3 mm. long, carinate, 

 cucuUate at the summit, drying green with yellow mar- 

 gins ; the inner sepals smaller, yellow ; stamens 3-6 ; 

 „., <.„ . V V .,/ achene smooth, shining, included. (P. camporum of 

 ?t»^ ,lTvS"° '^ '^- auth. in part, not Meisn.) —Sandy soil, Me. and Mass., 



btem-ieai X /s. j^^^j . ^_ p^_ . m_ ^^ jyiinn., Tex., and westw. Fig. 



712. Forma ATLiNTicnm Eobinson. Sepals 5 or rarely 6, roseate, not drying 

 yellow, nor even yellowish. — Frequent on the coast, Me. to R. I. In habit 

 identical with the typical western form. i 



8. P. tfinue Michx. Stem angled, erect (1.5-4 dm. high), ij 



gla,brous, or slightly scahrous at the nodes ; leaves narrowly Ian- m 



ceolate to linear, 2-5 cm. long, acute at each end, j| 



strongly plicate; flowers usually solitaiy, nearly i 



sessile, erect ; stamens 8 ; achene included, dull ' 



hlack. — Dry soil, s. Me. to S. C, w. to Man., Minn., '13- ?■ tenue. 

 Neb., and Tex. Fig. 713. Stem-leaf (cut 



9. P. Dougiasil Greene. Stem angled, erect; to show plicate 

 leaves lanceolate to linear, acute at each end, slightly ""'"''«) " %• 

 rigid, the margins revolute but the surface not plicate ; pedicels 

 short but slender ; flowers soon defiexed. — Rocky or sterile soil, 

 w. Me. to n. N. Y., Ont., and westw., local; common in Rocky 

 Mts. Fig. 714. 



711. P. erectum. 

 Flowering branch x % 



712. P. ramosissimum. 

 Fniiting calyx x 8. 



T14. P. Doug- 

 iasil. 

 Stem-leaf x %. 



§ 2. BIST6RTA [Toum.] L. Glabrous alpine perennials, with thich bulh-like 

 caudex and simple stems; flowers in a spike-like raceme; calyx colored, 

 deeply b-cleft ; stamens 8 ; styles S, long. 



10. P. viviparum L. Smooth, dwarf (4-35 cm. high), bearing a linear erect 

 spike of flesh-coloi'ed flowers (or often little red bulblets in their place) ; leaves 



