344 CONTBIBUTIONS FROM THE NATIONAL HERBARIUM. 



3. Melilotus alba Desr. in Lam. Encycl. 4: 63. 1797. Sweet clover. 



Type locality: Siberia. 



New Mexico: Frisco; Farmington; Pecos; Gila Hot Springs; Mesilla Valley; 

 Santa Fe; Albuquerque; Las Vegas. 



A common and troublesome weed in many parts of the State, especially in alkaline 

 soil. The plant is persistent and spreads rapidly. It is not infrequent in alfalfa 

 fields. It is said to be an excellent bee plant, and for this reason has been introduced 

 in several places, probably on the recommendation of not overscrupulous seedsmen. 



8. TRIFOLIUM L. Clover. 



Low perennial herbs, often tufted or diffuse, with palmately 3-foliolate leaves 

 (occasionally pinnately 3 to 5-foliolate); flowers usually in pedunculate heads, occa- 

 sionally elongated-spiciiorm; calyx with slender subulate teeth; corolla attached to 

 the stamen tube; pods small, membranous, indehiscent, often included in the per- 

 sistent calyx. 



key to the species. 

 Heads involucrate. 



Plants low, cespitose ; stems scapiform 1. T. parryi. 



Plants with elongated leafy stems. 



Corolla 12 to 15 mm. long; stems not much elongated, 



mostly erect ; peduncles glabrous 2. T. fendleri. 



Corolla 8 to 11 mm. long; stems much elongated, reclin- 

 ing; peduncles glabrous or pubescent. 

 Peduncles glabrous; involucre united well above 



the base, the divisions broad 3. T. lacerum. 



Peduncles pubescent below the involucre; invo- 

 lucre cleft almost to the base, the divisions 



very narrow 4. T. longicaule. 



Heads not involucrate. 



Stems leafy; plants tall or the stems long. 



Calyx glabrous; flowers white or nearly so. 



Stems creeping, stoloniferous 6. T. repens. 



Stems erect, tufted 7. T. hybridum. 



Calyx pubescent; flowers mostly purplish. 



Heads sessile 8. T. pratense. 



Heads long-peduncled. 



Flowers purplish; stems permanently pubes- 

 cent 9. T. neurophyllum . 



Flowers white; stems glabrous in age 12. T. rydbergii. 



Stems scapiform; plants low and cespitose. 



Calyx glabrous; heads 1 to 3-flowered 5. T. nanum. 



Calyx pubescent; heads several to many -flowered. 



Leaflets obovate, strongly veined, sharply dentate. . 10. T. subacaulescens. 

 Leaflets oblong to lanceolate, entire, not strongly 



veined 11. T. stenolobum. 



1. Trifolium parryi A. Gray, Amer. Journ. Sci. II. 33: 409. 1862. 

 Type locality: Rocky Mountains of Colorado. 



Range: Wyoming and Utah to Colorado and New Mexico. 



New Mexico: Pecos Baldy (Standley). Meadows, in the Arctic-Alpine Zone. 



2. Trifolium fendleri Greene, Pittonia 3: 221. 1897. 



Type locality: Near Santa Fe, New Mexico. Type collected by Fendler. 



Range: Colorado to New Mexico and Arizona. 



New Mexico: Santa Fe and Las Vegas mountains; Rio Pueblo; Albuquerque; 

 Mogollon Mountains; White and Sacramento mountains. Wet meadows, in the 

 Upper Sonoran and Transition zones. 



