[+] Outer petals wing-crested on the back.
2. C. flávula, DC. Pedicels slender, conspicuously bracted; corolla pale yellow, 3–4´´ long, spur very short; tips of the outer petals pointed, longer than the inner; crest 3–4-toothed; pods torulose, pendulous or spreading; seeds acutely margined, rugose-reticulated; aril loose.—Penn. to Minn., and southward.
3. C. micrántha, Gray. Pedicels short and bracts small; corolla pale yellow, 4´´ long, with short spur and entire crest, or flowers often cleistogamous and much smaller, without spur or crest; pods ascending, torulose; seeds obtuse-margined, smooth and shining.—N. Car., Mo., Minn., and southward.
4. C. crystállina, Engelm. Pedicels short, erect; corolla bright yellow, 8´´ long, the spur nearly as long as the body; crest very broad, usually toothed; pods terete, erect, densely covered with transparent vesicles, seeds acutely margined, tuberculate.—S. W. Mo. and southward.
[+][+] Outer petals merely carinate on the back, not crested.
5. C. aùrea, Willd. (Golden C.) Corolla golden-yellow, ½´ long, the slightly decurved spur about half as long, shorter than the pedicel; pods spreading or pendulous, becoming torulose; seeds obtuse-margined.—Rocky banks, Vt. to Penn., Mo., Minn., and westward.
Var. occidentàlis, Engelm. Flowers rather larger, the spur nearly as long as the body; pods less torulose, on short pedicels; seeds acutish on the margin.—Neb. and Kan. to W. Tex. and westward.
4. FUMÀRIA, Tourn. Fumitory.
Corolla 1-spurred at the base. Style deciduous. Fruit indehiscent, small, globular, 1-seeded. Seeds crestless.—Branched and leafy-stemmed annuals, with finely dissected compound leaves, and small flowers in dense racemes or spikes. (Name from fumus, smoke.)
F. officinàlis, L. (Common Fumitory.) Sepals ovate-lanceolate, acute, sharply toothed, narrower and shorter than the corolla (which is flesh-color tipped with crimson); fruit slightly notched.—Waste places, about dwellings. (Adv. from Eu.)