Rosackia. LEGUMINOSJE. 133 



Sparingly naturalized. In cultivation it is probably the most valuable of forage plants for 

 warm and dry regions. The root often reaches a depth of 8 or 10 feet, and may endure for many 

 years. The herbage is very nutritious, and on deep soils with proper moisture it yields several 

 crops, in some parts of the State growing and blooming nearly through the year. There is no 

 specific difference between the English and German Lucerne and the Spanish and Chilian Alfalfa, 

 but it is popularly believed that the Chilian variety is better adapted to this State than the 

 European. 



2. M. denticulata, Willd. (BUR-CLOVER.) Annual, nearly glabrous, pros- 

 trate or ascending : leaflets cuneate-obovate or obcordate, toothed above : flowers 

 small, yellow, usually 3 to 8 in a small cluster : pods spiral, strongly reticulated ; 

 the margin thin, keeled, armed with a double row of curved or hooked prickles. 



Native of the Mediterranean region, and naturalized in most warm countries. It is valuable as 

 a forage plant, but the burs are a source of great damage to wool. It fruits abundantly and the 

 pods are eaten with great avidity by cattle and sheep, remaining good until the winter-rains. 



3. M. lupulina, Linn. Annual, pubescent, procumbent : leaflets cuneate-obo- 

 vate, toothed above : flowers very small, yellow, in short spikes : pods small, reni- 

 form, 1 -seeded, not armed, black when ripe. 



Sparingly introduced. 



8. HOSACKIA, Douglas. 



Calyx-teeth nearly equal, usually shorter than the tube. Petals free from the 

 stamens, nearly equal : standard ovate or roundish, the claw often remote from the 

 others ; wings obovate or oblong ; keel somewhat incurved, obtuse or somewhat 

 acutely beaked. Stamens diadelphous ; anthers uniform. Style incurved. Pod 

 linear, compressed or somewhat terete, sessile, several-seeded, partitioned between 

 the seeds. Herbaceous or rarely suffrntescent ; leaves pinnate, 2 - many-foliolate ; 

 stipules minute and gland-like, rarely scarious or foliaceous ; flowers yellow or 

 reddish, in axillary sessile or pedunculate umbels. Gray, Proc. Acad. Philad. 

 1863, 346 ; Watson, Bot. King Exp. 432. 



A North American genus of about 30 species, almost wholly confined to the western side of the 

 continent and ranging from Mexico to British Columbia. It is very closely related to Lotus of 

 the Old World, to which genus the section Microlotus is referred by Bentham & Hooker, Gen. PL 

 i. 490, with apparently good reason. The yellow or orange color of the fresh flowers in most of the 

 species turns to reddish or reddish-brown in drying. The section Syrmatium is the most strongly 

 characterized and might well be considered generically distinct. 



* Pod shortly acute, linear and many-seeded, straight, glabrous (except in H. rigida) : seeds sub- 

 orbicular : flowers and fruit not reflexed : peduncles long : keel broad above, mostly obtuse. 



Stipules large and foliaceous : perennials. 



Densely villous : leaflets 9 to 15 : bract leaf-like, near the umbel. 1. H. INCANA. 



Less villous, viscid : leaflets 15 to 21 : bract leaf- like, distant. 2. H. STIPTJLARIS. 



Stipules scarious, mostly small : perennials. 



Stout, nearly glabrous : leaflets 9 to 15, thickish : bract below the um- 

 bel : calyx-teeth short : pod thick. 3. H. CRA8SIFOLIA. 

 Glabrous : leaflets 5 to 9 : bract usually none or small : teeth half as 



long as the tube : pod slender : wings usually white. 4. H. BICOLOR. 



Glabrous, low : bract 1 - 3-foliolate, at the umbel : teeth longer : pod 



shorter : keel and wings purplish. 5. H. GRACiLis. 



Appressed-puberalent : bract at the umbel, usually 1-foliolate : flowers 



yellow and purplish. 6. H. OBLONGIFOLIA. 



Silky-pubescent : bract at the umbel, usually 1-foliolate : keel and 



wings white. 7. H. TORREYI. 



Stipules reduced to blackish glands. 



Perennials, appressed-pubescent : flowers 1 to 8, rather large. 



Mostly tall and stout : leaflets 5 to 7 ; rhachis elongated : pod long, 



glabrous. 8. H. GRANDIFLORA. 



More slender : leaflets 3 to 5 ; rhachis short or none : pod shorter, 



pubescent. 9. H. RIGIDA. 



