CIIENOPODIACEAE 79 



13. P. exsertum Small. Annual, l°-3° high : leaves lanceolate, 

 acute, short-petioled : stamens 5-6: achene 2-3 times the length of the 

 calyx. — Muddy banks of Eock Creek near its mouth, and near Indepen- 

 dence. Not common. August-September. 



14. P. ramosissimum Michx. Annual, l°-4° high : leaves linear- 

 lanceolate, acute, short-petioled : stamens 6 : achene sometimes slightly 

 exserted. — Common in open grounds. August-Septemb">r. 



15. P. tenue Michx. Annual, ¥-\2' high, slender: leaves linear- 

 lanceolate, acute, short-petioled : flowers erect : stamens 8 : achene in- 

 cluded. — On wet hillsides north of Lee's Summit and south of Grain 

 Valley. Local. July-September. 



16. P. Convolvulus L. Climbing Buckwheat. Annual, twining 

 or procumbent, scurfy: leaves ovate-sagittate: flowers in pedicelled 

 clusters: outer calyx lobes keeled, but not winged. — Frequent in waste 

 places and along railroads. June-August. 



17. P. scandens L. Climbing Buckwheat. Perennial, strongly 

 climbing, smooth : leaves ovate cordate at base, loug-petioled : racemes 

 numerous, panicled and leafy: outer calyx lobes strongly winged, b"-W 

 long. — Abundant in thickets. July-October. 



18. P. sagittatum L. Tear Thumb. Annual : stems climbing, 

 thickly covered with sharpreflexed prickles : leaves lanceolate-sagittate, 

 short-petioled : flowers in capitate clusters. — In bogs near Buckner and 

 Sibley. Locally abundant. July-October. 



Family 38. CHENOPODIACEAE Dumort. 

 Weedy herbs with alternate, non-stipulate leaves. Flowers small, 

 greenish, without scarious bracts. Calyx 2-5-lobed or parted, or of but 

 one sepal. Stamens as many as calyx lobes, or sometimes fewer. Ovary 

 superior, 1-celled, 1-ovuled. Styles or stigmas 1-5. Fruit a utricle, with 

 a thin or thick covering (pericarp). 



Leaves not rigid and spiny tipped. 



Pistillate flowers not enclosed by bractlets. 

 Sepals three to five. 



Fruiting calyx strongly winged. 2. Cycloloma. 



Fruiting calyx not strongly winged. 



Leaves not linear and ciliate. 1. Chenopodium. 



Leaves linear and ciliate. 5. KoCHlA. 



Sepals solitary. 

 Leaves toothed. 3. Monolepis. 



Leaves entire. ' 6. CoRiSPERMUM. 



Pistillate flowers enclosed by two bractlets. 4. Atriplex. 



Leaves rigid and spiny tipped. 7. Salsola. 



1. CHENOPODIUM L. 



"Weeds with perfect sessile flowers in panicled clusters. Sepals and 

 stamens each 3-5. Styles 2-3. Calyx lobes enveloping the fruit, which 

 is enclosed by a thin covering (pericarp). 



