Thermopsis. LEGUMINOS^. 223 



Suborder II. C.ES ALPINE.^. 



Flower more or less irregular. Perigynous disk lining the tube or base of the 

 calyx. Petals imbricated in the bud, the superior one (answering to the standard) 

 within the lateral ones. Stamens 10 or fewer, distinct. Seeds sometimes with 

 albumen. Radicle not incurved. 



* Corolla seemingly papilionaceous. 



17. Cercis. Trees or shrubs, with simple rounded leaves, and lateral fascicles of rose-purple 



flowers. Calyx barely 5-toothed. 



* * Corolla not at all papilionaceous, yellow. Calyx 5-parted. Seeds with albumen. 



18. Cassia. Herbs or sometimes shrubs, with simply and abruptly pinnate leaves. Anthers 



fixed by the base, mostly opening by terminal pores, either 10 and imeijual or some of 

 the upper ones imperfect, abortive, or wanting. Calyx imbricated in the bud. 



19. Parkinsonia. Somewhat spinescent shrubs or trees, with twice pinnate (or apparently only 



] annate) leaves : leaflets small. Anthers 10, fixed by the middle, opening lengthwise. 

 Calyx valvate. 



Suborder III. MIMOSE.E. 



Flowers regular, small, and numerous in spikes or heads, l^o perigynous disk. 

 Calyx and corolla valvate in the bud, 4 - 5-merous. Stamens as many or twice as 

 many as the petals, or numerous, hypogynous. Seeds mostly without albumen. 

 Radicle not incurved. Leaves usually twice pinnate. 



20. Prosopis. Stamens 10. Petals distinct or becoming so. More or less spiny shrubs or trees. 



Flowers greenish. 



21. Acacia. Stamens indefinitely numerous. Petals united below. Flowers yellow. 



1. THERMOPSIS, R. Brown. 

 Calyx campanulate, cleft to the middle ; teeth equal or the two upper ones united. 

 Standard roundish, shorter than the oblong wdngs, the sides reflexed : keel nearly 

 straight, obtuse, its petals somewhat united, equalling the wings. Stamens distinct. 

 Style slightly incurved : stigma minute. Pod linear to oblong-linear, much com- 

 pressed, few - many-seeded, shortly stipitate or nearly sessile, straight or incurved. 

 — Stout perennial herbs, with erect clustered stems ; leaves digitately 3-foliolate, 

 with free foliaceous stipules, shortly petioled ; leaflets entire ; flowers large, yellow, 

 in terminal racemes, with persistent herbaceous bracts ; pedicels short, mostly soli- 

 tary, naked. 



About a dozen species, half belonging to Asia, and the rest to North America. Tliree of these 

 are confined to the Atlantic States and one to the Eocky Mountains. 



1. T. macrophylla, Hook. & Arn. Villous with long spreading hairs : stijniles 

 large, ovate ; leaflets oblong-elliptical, acute at each end, three inches long, glabrous 

 above, tomentose and villous beneath : calyx-teeth acuminate : stamens somewhat 

 persistent : pod villous, shortly stipitate, oblong-linear, nearly 2 inches long and 4 

 lines broad, straight, erect, 4- 5-seeded. — B()t. Beechey, 329; Torr. & Gray, Fl. 

 i. 388. 



Collected by Douglas in California, but the locality luiknown. All the specimens from other 

 collections that have been referred to the species, seem to belong to the next. 



2. T. Californica, Watson. Woolly-tomentose throughout : stipules lanceo- 

 late ; leaflets obovate to oblanceolate, an inch or two long, acute or obtuse, equally 

 tomentose on both sides : bracts broad at base, mostly ovate : pod very pubescent. 



