264 MISC. PUBLICATION 42 3, U. S. DEPT. OF AGRICULTURE 



3. Flowers solitary or loosely clustered, in dichotomous cymes; odor pro- 

 nounced but not fetid (4). 

 4. Plant glabrous or sparsely puberulent, subspinescent at matu- 

 rity; calyx resinous-granular, the lobes corniculate-append- 



aged 3. C. incisum. 



4. Plant copiously glandular-hirtellous; calyx not or scarcely granular, 



the lobes not appendaged 4. C. botrys. 



2. Foliage and inflorescence not glandular (5). 



5. Plant not farinose, glabrous throughout or very nearly so, green, often 

 tinged with red; leaf blades thin, coarsely toothed or pinnatifid, 

 deltoid or rhombic-ovate, cuneate at base; seeds mostly verti- 

 cal 5. C. EUBRUM. 



5. Plant more or less farinose, at least on the lower surface of the leaves, 

 or on the calyx (6) . 

 6. Seeds mostly vertical, their surface minutely roughened; inflorescence 

 often sparsely pilose (some of the hairs more or less elongate); 

 leaf blades green above, densely white-farinose beneath, sinuate- 

 dentate 6. C. GLAUCUM. 



6. Seeds all or mostly horizontal; inflorescence with scaly (farinose) 

 pubescence only, none of the hairs elongate (7). 

 7. Plant bright green, the lower leaf surface and inflorescence sparsely 

 farinose; flowers mostly in axillary panicles not or not greatly 

 surpassing the leaf blades; leaf blades (at least the lower ones) 

 broadly deltoid or rhombic-ovate, coarsely and often sharply 

 dentate; pericarp closely adherent to the sharp-edged seed. 



7. C. MURALE. 

 7. Plant not bright green, or the flowers mostly in elongate, terminal 

 and axillary panicles, or the pericarp not closely adherent and the 

 seeds shiny (8). 

 8. Leaf blades linear, lanceolate, or narrowly oblong, usually at least 

 3 times as long as wide, entire or slightly hastate; petioles 

 seldom more and usually less than one-third as long as the blade; 

 seeds not more than 1 mm. in diameter (9). 

 9. Pericarp free from the smooth, shiny, black seed. 



8. C. LEPTOPHYLLUM. 



9. Pericarp closely adherent to the seed (10). 



10. Leaf blades prevailingly linear or linear-lanceolate; calyx 

 open at full maturity, its lobes not strongly carinate. 



9. C. INAMOENUM. 



10. Leaf blades prevailingly oblong or oblong-lanceolate; calyx 

 partly closed at maturity, its lobes strongly carinate. 



10. C. HIANS. 



8. Leaf blades broadly oblong, lance-ovate, or broader, usually less 



than 3 times as long as wide; petioles seldom less and usually 



more than one-third as long as the blade (11). 



11. Leaf blades often more than 3 cm. long, considerably longer than 



wide, mostly deltoid or rhombic-ovate, the margins sinuate 



or dentate; plant usually green, seldom densely farinose (12). 



12. Seeds smooth and very shiny 11. C. album. 



12. Seeds minutely alveolate, not very shiny. 



12. C. BERLANDIERI. 



11. Leaf blades usually less than 3 cm. long, not, or but slightly, 

 longer than wide, deltoid, mostly subhastately toothed or 

 lobed near the base, the margins otherwise entire (13). 



13. Plants spreading, whitish, copiously farinose; branches stout, 



divergent; leaf blades thick: species of very similar 

 appearance (14). 

 14. Pericarp closely adherent to the seed; plant very ill-scented. 



13. C. WATSONI. 



14. Pericarp free; seeds smooth and shining, 14. C. incanum. 

 13. Plants erect, more or less virgate; branches ascending, 



usually slender; leaf blades thin (15). 



15. Pericarp free from the smooth, shiny, black seed; plant 



usually sparsely farinose and green _ 15. C. fremontii. 



15. Pericarp closely adherent to the seed; plant usually rather 



copiously farinose and whitish 16. C. arizonicum. 



