Part 2, 1920] 



FABACEAE: PSORALEAE 



Erect or ascending herbs or 

 shrubs with short spikes; 

 bracts not conspicuously 

 glandular - dotted ; keel- 

 petals united. 

 Flowers small; bracts 

 broadly ovate, purplish 

 and scarious-margined. 

 Flowers rather large ; bracts 

 lanceolate or subulate. 

 (P. oaxacana in) 

 Corolla white. 



Calyx-tube glabrous; leaves cuspidate; stipels 



conspicuous, subulate. 

 Calyx-tube pubescent, or at least puberulent; 

 leaves obtuse or minutely mucronate. 

 Leaflets more than 1 cm. long, oval or ob- 

 long; bracts shorter than the calyx, cadu- 

 cous. 

 Leaflets 3-5 mm. long. linear; bracts covering 

 the calyx, persistent. 

 Calyx-lobes subulate-tipped, usually longer than the tube, 

 rarely shorter than the same. 

 Plant herbaceous with a tap-root, woody, if at all, only at 

 the base. 

 Flowers reflexed, subtended by a pair of prominent 



gland-like bractlets. (See page 50.) 

 Flowers neither reflexed nor subtended by gland-like 

 bractlets. 

 Glands in the intervals of the calyx confluent. 

 Glands in the intervals of the calyx not confluent. 

 Plant glabrous, slender; bracts broadly obovate, 

 conspicuously glandular on the back and scar- 

 ious-margined. 

 Plant sericeous or villous, stout; bracts subulate 

 to ovate, neither conspicuously glandular 

 nor conspicuously scarious-margined. 

 Corolla yellow, fading pink or purplish; 



heads rarely long-peduncled. 

 Corolla blue or purple, ochroleucous only on 

 the banner; heads long-peduncled. 

 Plant more or less shrubby. 



Spikes terminating the stem or branches. 



Corolla purple or bluish to white, only the banner 

 often ochroleucous. 

 Leaves decidedly pubescent. 



Heads on very long peduncles; leaflets large 



and acute. 

 Heads short-peduncled or subsessile; leaflets 

 smalt, obtuse or rounded at the apex. 

 Leaves glabrous. 



Leaflets very numerous, 41-71; plants with 



elongate slender branches. 

 Leaflets fewer, 7-3 1 ; densely branched shrubs 

 with comparatively short branches. 

 Spike more or less elongate, distinctly 



peduncled. 

 Spike short and dense, subcapitate, sub- 

 sessile. 

 Corolla yellow, fading rose or purplish. 



Calyx not conspicuously glandular-dotted be- 

 tween the ribs; leaves glabrous; spikes short. 

 Calyx with a row of conspicuous yellow or brown 

 glands between the ribs; leaves more or less 

 pubescent. 

 Spikes subsessile at the end of short axillary branches, 

 as well as at the ends of the main branches. 



XVI. Citriodorae. 

 XXXIII. VersicolorEzs. 



XXVII. MUCRONATAE. 



XXVIII. Eysenhardtioides. 



XXIX. LUMHOLTZIANAE. 



IX. Lachnostachydes. 

 XIV. Flavae. 



XXX. PogonatheraE. 



XXXI. AurEAE. 

 XXXII. SERICEAE. 



XXXII. SERICEAE. 



XXXIII. Versicolores. 



XXXIV. Crassifoliae. 



XXXV. Lasiostachyae. 

 XXXVI. Formosae. 



XXXVII. Microphyllae. 



XXXVIII. Leucostomae. 

 XXXIX. Thyrsiflorae. 



X. Lagopodes 



Calyx-tube densely hairy, not conspicuously glandular-dotted. 



Calyx-tube glabrate or nearly so, with two rows of conspicuous yellowish glands. 



Rachis of the spike pubescent; plant 3-10 dm. high. 



Rachis of the spike glabrous; plant low, less than 3 dm. high. 



47. P. lagopina. 



48. P. Lagopus. 



49. P. exserta. 



