54 LEGUMINOS^. (pulse FAMILY.) 



colored; standard very broad. — From Central Colorado to Montana, and 

 westward along the plains of Snake and Columbia Rivers. 



Var. deeumbens, Watson. Stem stouter and more leafy : raceme 

 dense. — Proc. Am. Acad. viii. 532. L. deeumbens, Torr. L. laxiflorus, of 

 Hayd. Rep. 1872, L. laxiflorus, var. tenellus, of Hayd. Rep. 1871. From 

 Montana and Wyoming southward into New Mexico and Arizona. 



Var. argophyllus, Watson. More silky-pubescent ; the leaflets neai-ly 



equally so on both sides, longer than the petioles : flowers larger : caiyx decidedly 



spurred. — Proc. Am. Acad. viii. 532. S. Colorado and New Mexico. 



§ 2. Ovules 2 {rarely 3 or 4) : cotyledons broad and clasping afler germination, 



usually long persistent. Erect annuals : leaflets cuneate-oblong or -obovate : bracts 



persistent: pod ocate. — Platycarpos, Watson. 



12. L. pusillus, Pursh. Rather stout, 3 to 10 inches high, hirsute with 

 long spreading hairs : leaflets mostly 5, nearly smooth above, about half as long 

 as the petioles : racemes spicate, nearly sessile, 2 or 3 inches long : petals purple 

 or rose-color : pod very hirsute. — From the Upper Missouri to the Columbia 

 and southward east of the Sierras, to Arizona and New Mexico. 



13. L. Kingii, Watson. Resembles the last, but more slender and villous 

 with soft white hairs : racemes very short, fewflowered, on long slender peduncles : 

 pods and seeds smaller. — Proc Am. Acad. viii. 534. L. SUeri, Watson. Utah, 

 Colorado, and southward along the Rio Grande. 



4. TRIFOLIUM,! L. Clovee. 



Herbs with palmately compound leaves, stipules adnate to the petiole, 

 flowers in capitate racemes, spikes, or umbels, peduncles axillary or only 

 apparently terminal. — Watson Rev. Proc. Am, Acad. xi. 127. 

 * Leaflets 5 to 7 : heads not involucrate, terminal and axillary : flowers sessile : 

 calyx-tfetli fliiform, plumose : low or dwarf pei-ennials. 



1. T. megacephalum, Nutt. Stout, somewhat villous : leaflets cuneate- 

 oblong to obovate, obtuse, toothed : flowers very large (1 inch long), purplish, 

 in spicate heads : calyx half as long, the teeth very much longer than the tube : 

 pod stipitate, smooth. — Torr. & Gray, Fl. i. 315. Head-waters of the Mis- 

 souri, to Washington and N. E. California. 



* * Leaflets 3 : heads not involucrate, terminal : flowers sessile or nearly so: 



perennial or biennial. 

 4- Caulescent, often tall: calyx-teeth very narrow, shorter than the corolla."^ 



2. T. erioeephalura, Nutt. Villous with spreading hairs, or the stem 

 and leaves rarely glabrous : leaflets narrowly oblong or sometimes broader, 



1 Medicago sativa, L., has leaves pinnatelj' 3-tbliolate, the leaflets obovate-oblong. and 

 purple flowers. — Known as " Lucerne," and introduced into Wyoming, Utah, and westward. 



2 T. pratense, L., the common Red Clover, is becoming introduced and may be known by 

 its oval or obovate leaflets often notched at the end and marked above with a pale spot, broad 

 bristle-pointed stijuiles, ovate sessile heads of rose-purple flowers, and scarcely hairy calyx. 



T. repens, L., the White Clover, is also introduced, and may be known by its creeping 

 stems, axillary peduncles, inversely heart-shaped or merely notched leaflets, narrow stip- 

 ules, long petioles and peduncles, the short pedicels reflexed when old, and the white 

 flowers turning brownish in fading. 



