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NORTH AMERICAN FLORA 



[Volume 24 



Leaflets 9-13, oval or suborbicular, 15-20 mm. long, pale and puberulent 



beneath. 

 Leaflets 11-25, oblong to oval, 8-15 mm. long, glabrous, except the 

 veins beneath. 

 Peduncles, rachises, and branches neither hispid nor prickly. 



Leaflets thin, neither revolute-margtned nor prominently veined beneath ; 

 pod elliptic in cross-section, 15-20 mm. broad. 

 Branches, peduncles, and leaves more or less pubescent, at least 

 when young. 

 Leaflets short- villous on both sides; pod distinctly dotted by dark 



pustulate hair-bases. 

 Leaflets strigose or glabrate; pod not dotted. 

 Branches, peduncles, and leaves glabrous or rarely sparingly strigose 

 in D. carlhaginensis. 

 Leaflets 15-35 mm. long, rounded at both ends; corolla 18-20 mm. 



long. 

 Leaflets 7-15 mm. long. 



Corolla about 15 mm. long; leaflets mostly acute. 

 Corolla about 10 mm. long; leaflets rounded or retuse at the 

 apex. 

 Leaflets rather firm, strongly veined beneath, the margin somewhat 

 revolute; pod subrhombic in cross-section, about 1 cm. broad. 



1. D. echinala. 



2. D. sennioides. 



3. D. punctata. 



4. D . floribunda . 



5. D. robinioides. 



6. D. occidentalis. 



7. D. carthagenensis. 



8. D. suberosa. 



II. MinuTIFOLIae 



Branches, peduncles, rachises, and leaflets decidedly pilose-puberulent; 



lateral lobes of the calyx ovate. 

 Branches, peduncles, and rachises sparingly strigose-puberulent; leaflets 

 usually glabrous or nearly so, the pubescence most on the ribs beneath; 

 lateral lobes of the calyx lanceolate. 

 Bractlets oblanceolate; rachises not prickly. 

 Bractlets ovate; rachises usually minutely prickly. 



9. D. minutifolia. 



10. D. microphylla. 



11. D. spinosa. 



III. Glanduliferae 



Leaflets 7-33; pod oval in cross-section, the sutures not carinate. 



Calyx glabrous except theViliolate margins; leaflets hispidulous-ciliolate. 

 Pod 1 cm. broad, not much inflated; bractlets obovate or elliptic. 

 Pod 1.5 cm. broad, decidedly inflated; bractlets oblong. 

 Calyx glandular-pubescent; leaflets not hispidulous-ciliolate. 

 Corolla about 1 cm. long; leaflets puberulent or glabrate. 



Bracts and bractlets obovate; inflorescence merely glandular; 



pod oval to broadly oblong. 

 Bracts and bractlets oblanceolate or lanceolate; pod narrowly 

 oblong. 

 Corolla about 1.5 cm. long; leaflets villous. 

 Leaflets 5-9; pod sub-rhombic in cross-section, the sutures carinate. 



12. D. Thurheri. 



13. D. macrocarpa. 



14. D. racemosa. 



15. D. puberulenla. 



16. D. villosa. 



17. D. humilis. 



1. Diphysa echinata Rose, Contr. U. S. Nat. Herb. 

 12: 271. 1909. 



A low shrub; young branches hirsute-strigose and usually with yellowish bristles which 

 develop into weak prickles; stipules lance-linear, 5-7 mm. long; leaves 5-10 cm. long; rachis 

 sparingly hirsute in age, glabrate; leaflets 9-13, oval to suborbicular, 1.5-2 cm. long, very thin, 

 glabrous above, pale and puberulent or glabrate beneath; racemes 5-7 cm. long; peduncle and 

 pedicels hispid-prickly, the latter 1-2 cm. long; bracts linear, 5-7 mm. long; calyx glabrous, 

 the tube 6 mm. long; upper two lobes broadly ovate, rounded at the apex, ciliolate on the 

 margins, the lateral ones similar but narrower, the lowest one lanceolate, 4 mm. long. 



Type locality: Between Rosario and Colomas, Sinaloa. 

 Distribution; Known only from the type locality. 



2. Diphysa sennioides Benth.; Benth. & Oerst. Vidensk. 

 Meddel. 1853: 12. 1853. 



A shrub or small tree; branches sparingly hirsute-strigose, in age straw-colored; stipules 

 linear or lance-linear, falcate, 5-7 mm. long; leaves 5-10 cm. long; leaflets 11-25, oblong to 



