POLYGONACEAE (BUCKWHEAT FAMILY) 



359 



b c 



710. P. aviculare. 



a. Typical form x %. 



b. v. littorale x %. 



c. 8 tern -leaf of v. vegetum x %. 



d . Stem-leaf of v. angust. x %. 



Var. littorale (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 the typical 

 form and separated by no constant 

 character. (Eu.) FIG. 710 b. 



Var. vSgetum Ledeb. Larger, erect 

 or nearly so ; the leaves (often 3 cm. 

 long) oblong or narrowly elliptic, thin, 

 the margins crisped. Rich soil and 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 

 doubtless elsewhere. (Eu.) FIG. 710 d. 



6. P. er6ctum L. Stout, erect or ascending, yellowish- 

 green ; 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. rampsfssimum Michx. Flowering branch x 2/3. 

 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^ 

 cucullate at the summit, drying green with yellow mar- 

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

 achene smooth, shining, included. (P. camporum of 

 x auth. in part, not Meisn.) Sandy soil, Me. and Mass., 

 local; w. Pa. ; 111. to Minn., Tex., and westw. FIG. 

 712. Forma ATLANTICUM Robinson. Sepals 5 or rarely 6, roseate, not drying 

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

 identical with the typical western form. 



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

 glabrous, or slightly scabrous at the nodes ; leaves narrowly lan- 

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

 strongly plicate; flowers usually solitary, nearly 

 sessile, erect ; stamens 8 ; achene included, dull 

 black. Dry soil, s. Me. to S. C., w. to Man., Minn., ?13. P. tcnue. 

 Neb., and Tex. FIG. 713. stem-leaf (cut 



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

 leaves lanceolate to linear, acute at each end, slightly E x /3< 



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

 T14. P. Doug- short but slender; flowers soon deflexed. Rocky or sterile soil, 

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

 Mts. FIG. 714. 



711. P. erectum. 



712. P. ramosissimum. 

 Fruiting calyx x 3. 



Stem- 



lasii. 

 Stem-leaf x % 



2. BIST6RTA [Tourn.] L. Glabrous alpine perennials, with thick bulb-like 

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

 deeply &-cleft ; stamens 8 ; styles 3, long. 



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

 spike of flesh-colored flowers (or often little red bulblets in their place) : leaves 



